Antibiotic-resistant bacteria contamination in environments imposes great threats to human life health.This research aims to develop novel targeted antibacterial biochars for achieving high selectivity to kill pathoge...Antibiotic-resistant bacteria contamination in environments imposes great threats to human life health.This research aims to develop novel targeted antibacterial biochars for achieving high selectivity to kill pathogenic Escherichia coli(E.coli).The glycopolymer N-halamine-modified biochars(i.e.,BCPMA-Cl)were synthesized by the modification of biochars with poly[2-(methacrylamido)glucopyranose-coacrylamide](P(MAG-co-AM),followed by chlorination treatment.Based on the results of FTIR,turbidity,XPS,and UV–vis,BCPMA-Cl was successfully synthesized and demonstrated to be able to eliminate Staphylococcus aureus(S.aureus)and E.coli.Especially,BCPMA-Cl possessed extremely potent to specific-killing 10^(4) CFU·ml^(-1) of E.coli with lower hemolytic activity(<5%).Additionally,the antibacterial mechanisms of BCPMA-Cl against bacteria were contact-killing and release-killing contributed by active chlorine(i.e.,Cl^(+)).Therefore,this work provided a cost-effective and facile approach for preparation of functional biochars used for bacteria-specific therapeutic applications via livestock pollutants as well as showing a promising strategy to avoid bacterial resistance.展开更多
The aim of this study was to investigate adsorption and desorption characteristics of cadmium ion(Cd(II))by ash-free biochars and the adsorption mechanism.Biochars were prepared using peanut shell,bamboo,and Sophora j...The aim of this study was to investigate adsorption and desorption characteristics of cadmium ion(Cd(II))by ash-free biochars and the adsorption mechanism.Biochars were prepared using peanut shell,bamboo,and Sophora japonica Linn.Ash-free biochars were obtained by treating the biochars with acid elution.Adsorption and desorption data from batch experiments were analyzed using the Langmuir and Freundlich models and three adsorption kinetics models(i.e.,the Pseudo second-order,Elovich model,and the Intraparticle diffusion models).Results showed that the acid elution improved the pore structure of biochars,increased C content and aromatic functional group content,enhanced biochars hydrophobicity and adsorption capacity for Cd(II).Ash-free peanut shell biochar showed the best Cd(II)adsorption performance among the biochars.Adsorption of ash-free peanut shell biochar reached the equilibrium within 6 h with adsorption capacity of 34.2 mg/g.The adsorption conditions were optimized by orthogonal experiment.The Cd(II)removal efficiency achieved 91.7%with the optimized condition:initial concentration of Cd(II)of 50 mg/L,pH of 5,adsorption time of 12 h,and temperature of 15°C.Isothermal adsorption of Cd(II)by the six biochars was best described with the Langmuir model,indicating that the adsorption was a physical-chemical composite process.The desorption isotherm showed the hysteresis between adsorption and desorption.The main mechanism of Cd(II)adsorption of the ash-free biochars was a complex interaction of physical and chemical reactions,mainly including electrostatic adsorption,cationic-π,and ligand exchange.展开更多
Biochar derived from partial combustion of vegetation is ubiquitous and potentially effective in sequestration of environmental contaminants. Biochars were prepared by burning of red gum （Eucalyptus spp.） woodchips ...Biochar derived from partial combustion of vegetation is ubiquitous and potentially effective in sequestration of environmental contaminants. Biochars were prepared by burning of red gum （Eucalyptus spp.） woodchips at 450 and 850℃ （labeled as BC450 and BC850）. These two biochars were found to possess markedly different properties in terms of surface area and porosity. Short-term equilibration tests （24 hr） were conducted to assess the sorption-desorption behavior of pyrimethanil in the soil amended with various amounts of biochar of each type, with a special focus on the desorption behavior of the sorbed pesticide through four times successive desorption by dilution. Sorption coefficient and isotherm nonlinearity of the amended soils progressively increased with the content of biochar in the soil. Biochar BC850 with higher surface area and microporosity showed a stronger effect on the reversibility of sorption pesticide. The soils amended with 5% BC450 and 1% BC850 had nearly the same sorption capacity for pyrimethanil; however, their desorption processes were very different with 13.65% and 1.49% of the sorbed pesticide being released, respectively. This study suggested that biochar in soil could be an important factor for immobilization of a pesticide and thus affecting its environment fate in soil.展开更多
Biochar is increasingly proposed as a soil amendment, with reports of benefits to soil physical, chemical and biological properties. In this study, different biochars were produced from 6 feedstocks, including straw a...Biochar is increasingly proposed as a soil amendment, with reports of benefits to soil physical, chemical and biological properties. In this study, different biochars were produced from 6 feedstocks, including straw and poultry manure, at 3 pyrolysis temperatures （200, 300 and 500℃） and then added separately to a calcareous soil. Their effects on soil properties and maize growth were evaluated in a pot experiment. The biochars derived from crop straw had much higher C but smaller N concentrations than those derived from poultry manure. Carbon concentrations, pH and EC values increased with increasing pyrolysis temperature. Biochar addition resulted in increases in mean maize dry matter of 12.73% and NPK concentrations of 30, 33 and 283%, respectively. Mean soil pH values were increased by 0.45 units. The biochar-amended soils had 44, 55, 254 and 537% more organic C, total N, Olsen-P and available K, respectively, than the control on average. Both feedstocks and pyrolysis temperature determined the characteristics of the biochar. Biochars with high mineral concentrations may act as mineral nutrient supplements.展开更多
Two variable charge soils were incubated with biochars derived from straws of peanut, soybean, canola, and rice to investigate the effect of the biochars on their chemical properties and Pb（II） adsorption using batc...Two variable charge soils were incubated with biochars derived from straws of peanut, soybean, canola, and rice to investigate the effect of the biochars on their chemical properties and Pb（II） adsorption using batch experiments. The results showed soil cation exchange capacity （CEC） and pH significantly increased after 30 d of incubation with the biochars added. The incorporation of the biochars markedly increased the adsorption of Pb（II）, and both the electrostatic and non-electrostatic adsorption mechanisms contributed to Pb（II） adsorption by the variable charge soils. Adsorption isotherms illustrated legume- straw derived biochars more greatly increased Pb（II） adsorption on soils through the non-electrostatic mechanism via the formation of surface complexes between Pb（II） and acid functional groups of the biochars than did non-legume straw biochars. The adsorption capacity of Pb（II） increased, while the desorption amount slightly decreased with the increasing suspension pH for the studied soils, especially in a high suspension pH, indicating that precipitation also plays an important role in immobilizing Pb（II） to the soils.展开更多
Compost has been used to stabilise lead (Pb) in soil. However, compost contains a high level of dissolved organic matter (DOM) which may make Pb bioavailable in plant and thereby limiting its effectiveness and applica...Compost has been used to stabilise lead (Pb) in soil. However, compost contains a high level of dissolved organic matter (DOM) which may make Pb bioavailable in plant and thereby limiting its effectiveness and application. Addition of biochar to compost can reduce this effect. Rice husk (RH) and Cashew nut shell (CNS) biochars and compost-modified biochars were used in comparison to compost for stabilizing Pb in lead smelting slag (LSS)-contaminated soil (Pb = 18,300 mg/kg) in Nigeria. Efficiency of Pb stabilisation in control and amended soils was assessed using CaCl2 batch leaching experiment and plant performance. In pot experiments, maize plant was grown on the contaminated soil and on soil treated with minimum and optimum doses of the amendments singly and in combination for 6 weeks. Agronomical and chemical parameters of the plants were measured. CaCl2-extractable Pb in the untreated soil was reduced from 60 mg/kg to 0.55 mg/kg in RHB amended soils and non-detectable in other amended soils. RH-biochar/compost increased plant height, number of leaf and leaf area more than the others. Similarly, at minimum rate, it reduced root and shoot Pb by 91% and 86.0% respectively. Compost-modified rice husk biocharstabilised Pb in lead smelting slag contaminated soil reduced Pb plant uptake and improved plant growth. Lead stabilisation through the use of rice husk biochar with compost may be a green method for remediation of lead smelting slag-contaminated soil.展开更多
The sorption of ionizable benzotriazole(BTA) to corncob biochars pyrolyzed at different temperature(i.e., 300oC, 500oC and 800oC) was investigated in this study. Biochars produced at higher temperature showed higher s...The sorption of ionizable benzotriazole(BTA) to corncob biochars pyrolyzed at different temperature(i.e., 300oC, 500oC and 800oC) was investigated in this study. Biochars produced at higher temperature showed higher surface area, micropore volume and aromaticity. Consequently, the sorption of BTA changed from absorption to adsorption for biochars pyrolyzed at 300 oC and 800 oC, respectively. Solution p H affected speciation of BTA and surface charge properties of biochars. For BTA^0, H-bond, partition and micropore filling are dominant sorption mechanisms. For BTA-, it is suggested that negative charge-assisted H-bond plays an important role in sorption. Corncob biochar pyrolyzed at high temperature(e.g., 800 oC) showed the highest sorption affinity for BTA. Ca^(2+) in solution enhanced BTA^- and BTA^0 sorption through cation-bridge and surface complexation.展开更多
Biochars are low-cost and sustainable materials for environmental technologies.In this work,we pre-pared three biochars using pomelo peel(P-BC),algae(A-BC),and corncob(C-BC)to recover Cd^(2+)from wastewater via capaci...Biochars are low-cost and sustainable materials for environmental technologies.In this work,we pre-pared three biochars using pomelo peel(P-BC),algae(A-BC),and corncob(C-BC)to recover Cd^(2+)from wastewater via capacitive deionisation(CDI).A-BC possesses the highest amount of mesopores and nitro-gen functionality and attains the highest removal of Cd^(2+)via physical adsorption.For the electro-sorption capacity,C-BC and A-BC perform better capacitive removal of Cd^(2+)than P-BC due to the smaller charge-transfer and mass-transfer resistances.Also,this work investigated the impacts of surface morphology,cell voltage,NaCl,initial pH,and Cd^(2+)concentrations on Cd^(2+)capacitive removal and electrode regen-eration performances.The results indicated that A-BC and C-BC may be prospective materials for Cd^(2+)removal from wastewater by CDI.However,the presence of competing cations at high concentrations may influence the removal of Cd^(2+)at a low level,requiring the modification of A-BC and C-BC in future work.展开更多
Biochars were prepared by the pyrolysis of various H_(3)PO_(4) activated agricultural biomasses at 600℃and subsequently used as adsorbents for the removal of ciprofloxacin(CIP)from aqueous solution.Peanut shell-based...Biochars were prepared by the pyrolysis of various H_(3)PO_(4) activated agricultural biomasses at 600℃and subsequently used as adsorbents for the removal of ciprofloxacin(CIP)from aqueous solution.Peanut shell-based biochar(PSBC),corncob-based biochar(CCBC)and cotton-based biochar(CTBC)had high surface areas(571.0-1006.3 m^(2)/g),well-developed pore structures(mesopores with large pore volumes)and available adsorption functional groups(C=C,C-N and C-O-C).The CIP adsorption onto the biochars was investigated by batch experiments(kinetics,isotherms,thermodynamics,pH,etc.).Thermodynamics calculations showed the spontaneous(ΔG^(θ)<0)and endothermic(ΔH^(θ)>0)nature of the mechanism.In particular,CCBC exhibited high adsorption capacity(120.6 mg/g)of CIP in real lake water and it also had significant removal efficiency of other common pharmaceutical contaminants from real lake environ-ment,and even in a coexisting quintuple system.Finally,multiple interaction mechanisms of CIP adsorption onto aromatized biochar were explored combining characterization analysis and theoretical calculations.Elucidation of the mechanism of CIP adsorption onto biochar provides new insights into the assessment of the removal of pharmaceuticals from the aqueous environment.展开更多
Plastic pollution as a global environmental issue has become a research hotspot,among which the removal of inherent plasticizer(e.g.,phthalic acid esters,PAEs)received increasing attention.However,the effects of bioch...Plastic pollution as a global environmental issue has become a research hotspot,among which the removal of inherent plasticizer(e.g.,phthalic acid esters,PAEs)received increasing attention.However,the effects of biochars derived from different feedstocks on the adsorption of PAEs are poorly understood.Thus,the characteristics of biochars derived from six largely produced biomass wastes in China at 400°C,as well as their performance in adsorption of diethyl phthalate(DEP),one of frequently detected PAEs in aqueous environment,were investigated.The results indicated that the variation in feedstock type showed significant changes in the properties(e.g.,porosity,specific surface area,surface functional groups)of biochars,which affected DEP adsorption and desorption.Pseudosecond order and Freundlich models fitted the adsorption data well,and adsorption mechanisms mainly included hydrophobic effect,followed by micropore filling,hydrogen bonding,andπ-πEDA interactions.Adsorption thermodynamics revealed that the adsorption was a spontaneous and exothermic the adsorption capacities of DEP on these biochars slightly decreased with the increasing pH but increased with the increasing ionic strength.Among these biochars,the giant reed biochar with relatively higher DEP adsorption and low desorption exhibited the great efficiency for DEP removal as an environment-friendly sorbent.These results highlighted the significant roles of micropore filling and hydrogen bond in determining adsorption capacity of designed biochars prepared from selecting suitable agricultural straws and wetland plant waste to typical plasticizer.The findings are useful for producing designed biochars from different biomass wastes for plasticizer pollution control.展开更多
Biochar is considered a potential technology to enhance chemical fertilizer use efficiency through intensification of the interactions between nutrients and the functional groups on biochar surfaces.However,little is ...Biochar is considered a potential technology to enhance chemical fertilizer use efficiency through intensification of the interactions between nutrients and the functional groups on biochar surfaces.However,little is known about how the application of activated biochars mixed with urea influences nitrogen(N)mineralization and crop performance in paddy fields.Here,a sawdust-derived fresh biochar(FBC)(ca.400℃)was activated chemically with 15%hydrogen peroxide and biologically with a nutrient solution mixed with a soil inoculum to obtain a chemically activated biochar(CBC)and a biologically activated biochar(BBC),respectively.The chemical and surface properties of FBC,CBC,and BBC were evaluated using spectroscopic methods,i.e.,Fourier transform infrared spectroscopy and 13C nuclear magnetic resonance,and potentiometric charge determination.The N retention capacity of biochars and their interaction with urea hydrolysis were examined in a laboratory incubation experiment.Additionally,a field experiment was carried out in a paddy field with the biochars unmixed or mixed with urea at a 1:1 ratio.Our results showed that negative surface functional groups and negative charges were increased on both activated biochars,especially CBC.Both activated biochars contributed to a significant reduction in urea-biochar suspension pH and increased N retention in the incubation experiment.Despite the enhanced surface properties of the activated biochars,no similar increases in rice biomass and grain yield were observed for these biochars in the field experiment.However,rice biomass,grain yield,apparent N use efficiency,and agronomic N use efficiency were significantly higher with the application of the three biochars compared to no-biochar application.Altogether,the results indicate that the application of urea mixed with biochar could enhance crop performance,especially in the case of activated biochar,which would enhance N retention in the soil,reducing N loss.展开更多
Municipal wastewater sludge can be pyrolyzed as biochars to better use nutrients and stabilize carbon compared with other typical technologies,such as landfill and incineration.However,sludge-derived biochars might co...Municipal wastewater sludge can be pyrolyzed as biochars to better use nutrients and stabilize carbon compared with other typical technologies,such as landfill and incineration.However,sludge-derived biochars might contain large amounts of potentially toxic elements(PTEs),such as Zn,Cu,Cr,Ni,Pb,and As.The stability of PTEs in biochars might be improved by higher pyrolytic temperatures,which can be further improved by different modifications.Herein,PO4-modification at 300°C and Cl-modification at 700°C were carried out,respectively,to enhance the stability of PTEs.Various leaching tests have been performed to assess the stability of PTEs in biochars,including the synthetic precipitation leaching procedure(SPLP),toxicity characteristic leaching procedure(TCLP),diethylenetriamine pentaacetate(DTPA)extraction,and in vitro simple bioaccessibility extraction test(SBET).The morphological structure,elemental mapping,and mineral formation of the pristine and modified biochars were studied by scanning electron microscopy–energy-dispersive X-ray spectroscopy(SEM–EDS)and X-ray diffraction(XRD).Our results suggested that the leachability,mobility,plant-availability,and bioaccessibility of most PTEs were decreased by pyrolysis,yet the total contents of PTEs were elevated,especially at 700°C.Generally,modification by phosphates and MgCl2 enhanced the stability of PTEs in biochars.Nevertheless,it should be noted that higher bioaccessibility of PTEs was observed in biochars of P-modification than Cl-modification,which is associated with the dissolution of phosphate precipitates under acidic conditions(pH<2).Additionally,Cl-modification leads to higher plant-available Zn and Cu and bioaccessible Zn compared with the unmodified biochar produced at 700°C.展开更多
The structural reconstruction mechanism of lignin and cellulose-derived biochars during direct graphitization under ultra-high temperatures was intensively investigated.It was demonstrated that cellulose-derived char ...The structural reconstruction mechanism of lignin and cellulose-derived biochars during direct graphitization under ultra-high temperatures was intensively investigated.It was demonstrated that cellulose-derived char was almost composed of carbon microcrystallites,whereas lignin-derived char reserved some of its skeleton structures,and such structural difference played a vital role in the morphology of formed graphitic layers.The results illustrated that the graphitized lignin-derived sample under 2800℃had graphitic degree of 89.53%,interlayer spacing of 0.3363 nm and electronic conductivity of 104.6 S cm^(−1),while cellulose-derived sample had graphitic degree of 76.74%,layer distance of 0.3374 nm,and electronic conductivity of only 48.8 S cm^(−1).Combined with the results of structural analysis of the chars derived from lignin and cellulose,it was inferred that the stable and aromatic ring containing skeleton structure in lignin was beneficial to the ring-enlarging reconstruction and the formation of large areas of continuous graphitic layers during graphitizing process,leading to high electronic conductivity.Meanwhile,the interwoven microcrystallites in cellulose-derived char strongly restricted the expanding of continuous lamellar graphitic areas even at such ultra-high temperature,causing the formation of turbostratic structure with numerous structural defects as well,and finally resulting in relatively lower electronic conductivity.This work is expected to provide theoretical guidance for preparing high-performance functional carbon materials from lignocellulosic biomass.展开更多
Agricultural wastes are environmental hazards,as these wastes can catch fire,resulting in the loss of human and animal lives and properties.Alternatively,the wastes are dumped in large spaces,which are already limited...Agricultural wastes are environmental hazards,as these wastes can catch fire,resulting in the loss of human and animal lives and properties.Alternatively,the wastes are dumped in large spaces,which are already limited.Cementitious composites are quasi-brittle and develop cracks at the micro and nano level,which affect their strength,durability,and esthetics.Transforming agricultural wastes to biochar and using it as fibers in cementitious materials for crack arresting and enhancing fracture toughness is an environment-friendly approach.In this research,nano to microscale carbonaceous inert fibers(biochar)of millet and maize were prepared through pyrolysis followed by ball milling.The X-ray spectroscopy(EDX)revealed that 82.08%and 86.89%of the carbon content was retained in millet and maize,respectively.The scanning electron microscope(SEM)confirmed the presence of angular,flaky,and needle-like particles in the carbonaceous inerts,which may enhance the strength and the fracture response of the cementitious materials.These inerts were added individually to mortar specimens at dosage levels of 0,0.025%,0.05%,0.08%,0.2%and 1%by mass of cement.The dispersion of the synthesized nano inerts was ensured by UV–VIS spectroscopy.The compressive strength,flexural strength,porosity,and fracture toughness of cement mortar were evaluated.The carbonized nano intrusions reduced the porosity and density of the mortar specimens.The minimum porosity was noted with 1%and 0.08%dosages of millet and maize,respectively,whereas the minimum density was observed at 1%dosage for both.An increase in compressive and flexural strengths was also noticed.The compressive strength increased by 32%and 28%with 0.2%and 0.5%millet and maize,respectively.An increase of 168%and 114%in fracture toughness was noticed at optimized dosages of 0.5%and 1%of maize and millet,respectively.It is concluded that the addition of carbonaceous inert fibers of millet and maize resulted in light-weight porous mortars with enhanced strength and fracture toughness.The fracture toughness increases with dosage as the nanoparticles enhance the tortuosity.展开更多
The realization of a stable lithium-metal free(LiMF)sulfur battery based on amorphous carbon anode and lithium sulfide(Li_(2)S)cathode is here reported.In particular,a biomass waste originating full-cell combining a c...The realization of a stable lithium-metal free(LiMF)sulfur battery based on amorphous carbon anode and lithium sulfide(Li_(2)S)cathode is here reported.In particular,a biomass waste originating full-cell combining a carbonized brewer's spent grain(CBSG)biochar anode with a Li_(2)S-graphene composite cathode(Li_(2)S70Gr30)is proposed.This design is particularly attractive for applying a cost-effective,high performance,environment friendly,and safe anode material,as an alternative to standard graphite and metallic lithium in emerging battery technologies.The anodic and cathodic materials are characterized in terms of structure,morphology and composition through X-ray diffraction,scanning and transmission electron microscopy,X-ray photoelectron and Raman spectroscopies.Furthermore,an electrochemical characterization comprising galvanostatic cycling,rate capability and cyclic voltammetry tests were carried out both in half-cell and full-cell configurations.The systematic investigation reveals that unlike graphite,the biochar electrode displays good compatibility with the electrolyte typically employed in sulfur batteries.The CBSG/Li_(2)S70Gr30 full-cell demonstrates an initial charge and discharge capacities of 726 and 537 mAh g^(-1),respectively,at 0.05C with a coulombic efficiency of 74%.Moreover,it discloses a reversible capacity of 330 mAh g^(-1)(0.1 C)after over 300 cycles.Based on these achievements,the CBSG/Li_(2)S70Gr30 battery system can be considered as a promising energy storage solution for electric vehicles(EVs),especially when taking into account its easy scalability to an industrial level.展开更多
A novel photo-catalytic system composed of N-doped biochars(NBCs),MnFe_(2)O_(4) and sulfite activation under ultraviolet(NBCs/MnFe_(2)O_(4)/sulfite/UV)was constructed to realize the efficient eliminate of tetracycline...A novel photo-catalytic system composed of N-doped biochars(NBCs),MnFe_(2)O_(4) and sulfite activation under ultraviolet(NBCs/MnFe_(2)O_(4)/sulfite/UV)was constructed to realize the efficient eliminate of tetracycline(TC).As the carrier of MnFe_(2)O_(4),NBCs were synthesized from alfalfa,which has large specific surface area,graphite like structure and hierarchical porous structure.The adsorption isotherm indicated that NBCs/MnFe_(2)O_(4)-2:1 had the best adsorption performance for TC(347.56 mg g^(-1)).Through synergistic adsorption and photocatalysis,the removal rate of TC reached 84%,which was significantly higher than that of MnFe_(2)O_(4).Electrochemical impedance spectroscopy(EIS)and Photoluminescence(PL)characterization results showed that the introduction of NBCs improved the separation efficiency of photogenerated electron and hole pairs and enhanced the photocatalytic performance.Moreover,the adsorption,degradation mechanism and degradation path of TC by the catalyst were systematically analyzed by coupling HPLC–MS measurement with the theoretical calculation.Considering the advantages of excellent degradation performance,low cost,easy separation and environmental friendliness of NBCs/MnFe_(2)O_(4),this work was expected to provide a new path for the practical application of biochar.展开更多
Disposal of the pollutants arising from farming cattle and other livestock threatens the environment and public safety in diverse ways.Herein,we report on the synthesis of engineered biochars using cow dung as raw mat...Disposal of the pollutants arising from farming cattle and other livestock threatens the environment and public safety in diverse ways.Herein,we report on the synthesis of engineered biochars using cow dung as raw material,and investigating these biochars as antibacterial agents for water decontamination.By coating the biochars with N-halamine polymer and loading them with active chlorine (i.e.,Cl+),we were able to regulate them on demand by tuning the polymer coating and bleaching conditions.The obtained N-halamine-modified biochars were found to be extremely potent against Escherichia coli and Staphylococcus aureus.We also investigated the possibility of using these N-halamine-modified biochars for bacterial decontamination in real-world applications.Our findings indicated that a homemade filter column packed with N-halamine-modified biochars removed pathogenic bacteria from mining sewage,dairy sewage,domestic sewage,and artificial seawater.This proposed strategy could indicate a new way for utilizing livestock pollutants to create on-demand decontaminants.展开更多
Feedstock sources and pyrolysis temperatures affect the physicochemical and morphological properties of biochars.We evaluated biochars derived from switchgrass(SGB)and poultry litter(PLB)pyrolyzed at 350℃(SGB350,PLB3...Feedstock sources and pyrolysis temperatures affect the physicochemical and morphological properties of biochars.We evaluated biochars derived from switchgrass(SGB)and poultry litter(PLB)pyrolyzed at 350℃(SGB350,PLB350)and 700℃(SGB700,PLB700)to identify their potential ability in improving soil health.Except for SGB350,the pH of biochars was high(>10.0)and can be used as an amendment in acid soils.PLB700 had higher mineral content and nutrient availability due to its higher ash content(tenfold higher)and electrical conductivity.Surface functional groups responsible for metal retention were evidenced in all biochars.Cation exchange capacity(CEC),specific surface area(SSA),and microporosity more than doubled by increasing pyrolysis temperature from 350 to 700℃.The pH-buffering capacity measured through acid titration curve was better than that calculated with acid/alkali additions.Biochars pyrolyzed at 700℃ have much higher pH,CEC,SSA,and stronger buffering capacity,and thus are more promising to improve soil health and reduce contaminant bioavailability.展开更多
In China,substantial agricultural and garden wastes are burned yearly.This practice not only wastes resources but also pollutes air.Corn straw and poplar leaves are typical agricultural and garden waste in China.In th...In China,substantial agricultural and garden wastes are burned yearly.This practice not only wastes resources but also pollutes air.Corn straw and poplar leaves are typical agricultural and garden waste in China.In this study,corn straw and poplar leaves were used to prepare biochars with different pyrolysis temperatures(250℃,350℃,450℃,550℃and 650℃)and were labeled as CC(corn straw)and LC(poplar leaves),respectively.The biochars were characterized through elemental analysis,Brunauer-Emmett-Teller surface area analysis,scanning electron microscopy and Fourier transform infrared spectroscopy.Yield,ash content and biochar pH were also measured.Results showed that the two biochars possessed some similar characteristics with increasing pyrolysis temperature.These attributes included increased carbon content,biochar hydrophobicity,alkaline pH;decreased hydrogen and oxygen contents and polar functional group content;and enlarged surface area.The biochars also displayed some different characteristics,such as the obviously larger surface area of CC than that of LC at high pyrolysis temperatures and the regular holes of CC and irregular and disordered holes of LC.When biochars CC-650 and LC-650 were used as soil conditioners,the soil pH increased by 0.3 and 0.4 units,respectively,and the soil cation exchange capacity increased by 12.7%and 21.5%,respectively,with respect to those of the blank controls.展开更多
Lithium-sulfur batteries are emerging as sustainable replacements for current lithium-ion batteries.The commercial viability of this novel type of battery is still under debate due to the extensive use of highly react...Lithium-sulfur batteries are emerging as sustainable replacements for current lithium-ion batteries.The commercial viability of this novel type of battery is still under debate due to the extensive use of highly reactive lithium-metal anodes and the complex electrochemistry of the sulfur cathode.In this research,a novel sulfur-based battery has been proposed that eliminates the need for metallic lithium anodes and other critical raw materials like cobalt and graphite,replacing them with biomass-derived materials.This approach presents numerous benefits,encompassing ample availability,cost-effectiveness,safety,and environmental friendliness.In particular,two types of biochar-based anode electrodes(non-activated and activated biochar)derived from spent common ivy have been investigated as alternatives to metallic lithium.We compared their structural and electrochemical properties,both of which exhibited good compatibility with the typical electrolytes used in sulfur batteries.Surprisingly,while steam activation results in an increased specific surface area,the non-activated ivy biochar demonstrates better performance than the activated biochar,achieving a stable capacity of 400 mA h g^(−1)at 0.1 A g^(−1)and a long lifespan(>400 cycles at 0.5 A g^(−1)).Our results demonstrate that the presence of heteroatoms,such as oxygen and nitrogen positively affects the capacity and cycling performance of the electrodes.This led to increased d-spacing in the graphitic layer,a strong interaction with the solid electrolyte interphase layer,and improved ion transportation.Finally,the non-activated biochar was successfully coupled with a sulfur cathode to fabricate lithium-metal-free sulfur batteries,delivering a specific energy density of~600 Wh kg^(−1).展开更多
基金supported by the National Natural Science Foundation of China(21304044,51663019,and 22062017)the Natural Science Foundation of Inner Mongolia Autonomous Region(2015MS0520,2019JQ03 and 2019BS02004)+2 种基金the State Key Laboratory of Medicinal Chemical Biology(201603006 and 2018051)the State Key Laboratory of Polymer Physics and Chemistry(2018-08)the Program of Higher-Level Talents of Inner Mongolia University(30105-125136)。
文摘Antibiotic-resistant bacteria contamination in environments imposes great threats to human life health.This research aims to develop novel targeted antibacterial biochars for achieving high selectivity to kill pathogenic Escherichia coli(E.coli).The glycopolymer N-halamine-modified biochars(i.e.,BCPMA-Cl)were synthesized by the modification of biochars with poly[2-(methacrylamido)glucopyranose-coacrylamide](P(MAG-co-AM),followed by chlorination treatment.Based on the results of FTIR,turbidity,XPS,and UV–vis,BCPMA-Cl was successfully synthesized and demonstrated to be able to eliminate Staphylococcus aureus(S.aureus)and E.coli.Especially,BCPMA-Cl possessed extremely potent to specific-killing 10^(4) CFU·ml^(-1) of E.coli with lower hemolytic activity(<5%).Additionally,the antibacterial mechanisms of BCPMA-Cl against bacteria were contact-killing and release-killing contributed by active chlorine(i.e.,Cl^(+)).Therefore,this work provided a cost-effective and facile approach for preparation of functional biochars used for bacteria-specific therapeutic applications via livestock pollutants as well as showing a promising strategy to avoid bacterial resistance.
基金supported by the Key Laboratory of Environmental Pollution Control and Restoration Technology of Guangdong province(2018K06)the project was supported by theMajor Science and Technology Projects of Gansu Province(18ZD2FA009)a National key research and development plan(2018YFC0507102).
文摘The aim of this study was to investigate adsorption and desorption characteristics of cadmium ion(Cd(II))by ash-free biochars and the adsorption mechanism.Biochars were prepared using peanut shell,bamboo,and Sophora japonica Linn.Ash-free biochars were obtained by treating the biochars with acid elution.Adsorption and desorption data from batch experiments were analyzed using the Langmuir and Freundlich models and three adsorption kinetics models(i.e.,the Pseudo second-order,Elovich model,and the Intraparticle diffusion models).Results showed that the acid elution improved the pore structure of biochars,increased C content and aromatic functional group content,enhanced biochars hydrophobicity and adsorption capacity for Cd(II).Ash-free peanut shell biochar showed the best Cd(II)adsorption performance among the biochars.Adsorption of ash-free peanut shell biochar reached the equilibrium within 6 h with adsorption capacity of 34.2 mg/g.The adsorption conditions were optimized by orthogonal experiment.The Cd(II)removal efficiency achieved 91.7%with the optimized condition:initial concentration of Cd(II)of 50 mg/L,pH of 5,adsorption time of 12 h,and temperature of 15°C.Isothermal adsorption of Cd(II)by the six biochars was best described with the Langmuir model,indicating that the adsorption was a physical-chemical composite process.The desorption isotherm showed the hysteresis between adsorption and desorption.The main mechanism of Cd(II)adsorption of the ash-free biochars was a complex interaction of physical and chemical reactions,mainly including electrostatic adsorption,cationic-π,and ligand exchange.
文摘Biochar derived from partial combustion of vegetation is ubiquitous and potentially effective in sequestration of environmental contaminants. Biochars were prepared by burning of red gum （Eucalyptus spp.） woodchips at 450 and 850℃ （labeled as BC450 and BC850）. These two biochars were found to possess markedly different properties in terms of surface area and porosity. Short-term equilibration tests （24 hr） were conducted to assess the sorption-desorption behavior of pyrimethanil in the soil amended with various amounts of biochar of each type, with a special focus on the desorption behavior of the sorbed pesticide through four times successive desorption by dilution. Sorption coefficient and isotherm nonlinearity of the amended soils progressively increased with the content of biochar in the soil. Biochar BC850 with higher surface area and microporosity showed a stronger effect on the reversibility of sorption pesticide. The soils amended with 5% BC450 and 1% BC850 had nearly the same sorption capacity for pyrimethanil; however, their desorption processes were very different with 13.65% and 1.49% of the sorbed pesticide being released, respectively. This study suggested that biochar in soil could be an important factor for immobilization of a pesticide and thus affecting its environment fate in soil.
基金supported by the National Natural Science Foundation of China (41171211)the Special Fund for Agro-Scientific Research in the Public Interest, China (201303095-2)
文摘Biochar is increasingly proposed as a soil amendment, with reports of benefits to soil physical, chemical and biological properties. In this study, different biochars were produced from 6 feedstocks, including straw and poultry manure, at 3 pyrolysis temperatures （200, 300 and 500℃） and then added separately to a calcareous soil. Their effects on soil properties and maize growth were evaluated in a pot experiment. The biochars derived from crop straw had much higher C but smaller N concentrations than those derived from poultry manure. Carbon concentrations, pH and EC values increased with increasing pyrolysis temperature. Biochar addition resulted in increases in mean maize dry matter of 12.73% and NPK concentrations of 30, 33 and 283%, respectively. Mean soil pH values were increased by 0.45 units. The biochar-amended soils had 44, 55, 254 and 537% more organic C, total N, Olsen-P and available K, respectively, than the control on average. Both feedstocks and pyrolysis temperature determined the characteristics of the biochar. Biochars with high mineral concentrations may act as mineral nutrient supplements.
基金supported by the Key Technoligies R&D Program of China during the 12th Five-Year Plan period (2012BAJ24B06)the National Natural Science Foundation of China (41230855)
文摘Two variable charge soils were incubated with biochars derived from straws of peanut, soybean, canola, and rice to investigate the effect of the biochars on their chemical properties and Pb（II） adsorption using batch experiments. The results showed soil cation exchange capacity （CEC） and pH significantly increased after 30 d of incubation with the biochars added. The incorporation of the biochars markedly increased the adsorption of Pb（II）, and both the electrostatic and non-electrostatic adsorption mechanisms contributed to Pb（II） adsorption by the variable charge soils. Adsorption isotherms illustrated legume- straw derived biochars more greatly increased Pb（II） adsorption on soils through the non-electrostatic mechanism via the formation of surface complexes between Pb（II） and acid functional groups of the biochars than did non-legume straw biochars. The adsorption capacity of Pb（II） increased, while the desorption amount slightly decreased with the increasing suspension pH for the studied soils, especially in a high suspension pH, indicating that precipitation also plays an important role in immobilizing Pb（II） to the soils.
文摘Compost has been used to stabilise lead (Pb) in soil. However, compost contains a high level of dissolved organic matter (DOM) which may make Pb bioavailable in plant and thereby limiting its effectiveness and application. Addition of biochar to compost can reduce this effect. Rice husk (RH) and Cashew nut shell (CNS) biochars and compost-modified biochars were used in comparison to compost for stabilizing Pb in lead smelting slag (LSS)-contaminated soil (Pb = 18,300 mg/kg) in Nigeria. Efficiency of Pb stabilisation in control and amended soils was assessed using CaCl2 batch leaching experiment and plant performance. In pot experiments, maize plant was grown on the contaminated soil and on soil treated with minimum and optimum doses of the amendments singly and in combination for 6 weeks. Agronomical and chemical parameters of the plants were measured. CaCl2-extractable Pb in the untreated soil was reduced from 60 mg/kg to 0.55 mg/kg in RHB amended soils and non-detectable in other amended soils. RH-biochar/compost increased plant height, number of leaf and leaf area more than the others. Similarly, at minimum rate, it reduced root and shoot Pb by 91% and 86.0% respectively. Compost-modified rice husk biocharstabilised Pb in lead smelting slag contaminated soil reduced Pb plant uptake and improved plant growth. Lead stabilisation through the use of rice husk biochar with compost may be a green method for remediation of lead smelting slag-contaminated soil.
基金supported by the National Natural Science Foundation of China (No. 41172223)
文摘The sorption of ionizable benzotriazole(BTA) to corncob biochars pyrolyzed at different temperature(i.e., 300oC, 500oC and 800oC) was investigated in this study. Biochars produced at higher temperature showed higher surface area, micropore volume and aromaticity. Consequently, the sorption of BTA changed from absorption to adsorption for biochars pyrolyzed at 300 oC and 800 oC, respectively. Solution p H affected speciation of BTA and surface charge properties of biochars. For BTA^0, H-bond, partition and micropore filling are dominant sorption mechanisms. For BTA-, it is suggested that negative charge-assisted H-bond plays an important role in sorption. Corncob biochar pyrolyzed at high temperature(e.g., 800 oC) showed the highest sorption affinity for BTA. Ca^(2+) in solution enhanced BTA^- and BTA^0 sorption through cation-bridge and surface complexation.
基金financially supported by the fellow-ship of the China Postdoctoral Science Foundation(No.2022TQ0088)the National Natural Science Foundation of China(No.52000053)+1 种基金Shenzhen Science and Technology Program(No.GXWD20201230155427003-20200821174135002,RCBS20210706092219047,and KQTD20190929172630447)the Open Project of State Key Laboratory of Urban Water Resources and Environment(No.2021TS28).
文摘Biochars are low-cost and sustainable materials for environmental technologies.In this work,we pre-pared three biochars using pomelo peel(P-BC),algae(A-BC),and corncob(C-BC)to recover Cd^(2+)from wastewater via capacitive deionisation(CDI).A-BC possesses the highest amount of mesopores and nitro-gen functionality and attains the highest removal of Cd^(2+)via physical adsorption.For the electro-sorption capacity,C-BC and A-BC perform better capacitive removal of Cd^(2+)than P-BC due to the smaller charge-transfer and mass-transfer resistances.Also,this work investigated the impacts of surface morphology,cell voltage,NaCl,initial pH,and Cd^(2+)concentrations on Cd^(2+)capacitive removal and electrode regen-eration performances.The results indicated that A-BC and C-BC may be prospective materials for Cd^(2+)removal from wastewater by CDI.However,the presence of competing cations at high concentrations may influence the removal of Cd^(2+)at a low level,requiring the modification of A-BC and C-BC in future work.
基金supported by grants from the National Natural Science Foundation of China(grant Nos.22068002,22178054 and 22176032)Training plan for academic and technical leaders of major disciplines in Jiangxi Province-youth talent project(grant No.20212BCj23001)Natural Science Foundation of Jiangxi Province(grant No.20212ACB203002).
文摘Biochars were prepared by the pyrolysis of various H_(3)PO_(4) activated agricultural biomasses at 600℃and subsequently used as adsorbents for the removal of ciprofloxacin(CIP)from aqueous solution.Peanut shell-based biochar(PSBC),corncob-based biochar(CCBC)and cotton-based biochar(CTBC)had high surface areas(571.0-1006.3 m^(2)/g),well-developed pore structures(mesopores with large pore volumes)and available adsorption functional groups(C=C,C-N and C-O-C).The CIP adsorption onto the biochars was investigated by batch experiments(kinetics,isotherms,thermodynamics,pH,etc.).Thermodynamics calculations showed the spontaneous(ΔG^(θ)<0)and endothermic(ΔH^(θ)>0)nature of the mechanism.In particular,CCBC exhibited high adsorption capacity(120.6 mg/g)of CIP in real lake water and it also had significant removal efficiency of other common pharmaceutical contaminants from real lake environ-ment,and even in a coexisting quintuple system.Finally,multiple interaction mechanisms of CIP adsorption onto aromatized biochar were explored combining characterization analysis and theoretical calculations.Elucidation of the mechanism of CIP adsorption onto biochar provides new insights into the assessment of the removal of pharmaceuticals from the aqueous environment.
基金supported by the Shandong Provincial Major Science and Technology Innovation Project(China)(2019JZZY020302)the National Natural Science Foundation of China(Grant No.22106136)+1 种基金Hainan Provincial Joint Project of Sanya Yazhou Bay Science and Technology City(China)(220LH061)National Science Fund for Distinguished Young Scholars of Shandong Province(China)(ZR2021JQ13).
文摘Plastic pollution as a global environmental issue has become a research hotspot,among which the removal of inherent plasticizer(e.g.,phthalic acid esters,PAEs)received increasing attention.However,the effects of biochars derived from different feedstocks on the adsorption of PAEs are poorly understood.Thus,the characteristics of biochars derived from six largely produced biomass wastes in China at 400°C,as well as their performance in adsorption of diethyl phthalate(DEP),one of frequently detected PAEs in aqueous environment,were investigated.The results indicated that the variation in feedstock type showed significant changes in the properties(e.g.,porosity,specific surface area,surface functional groups)of biochars,which affected DEP adsorption and desorption.Pseudosecond order and Freundlich models fitted the adsorption data well,and adsorption mechanisms mainly included hydrophobic effect,followed by micropore filling,hydrogen bonding,andπ-πEDA interactions.Adsorption thermodynamics revealed that the adsorption was a spontaneous and exothermic the adsorption capacities of DEP on these biochars slightly decreased with the increasing pH but increased with the increasing ionic strength.Among these biochars,the giant reed biochar with relatively higher DEP adsorption and low desorption exhibited the great efficiency for DEP removal as an environment-friendly sorbent.These results highlighted the significant roles of micropore filling and hydrogen bond in determining adsorption capacity of designed biochars prepared from selecting suitable agricultural straws and wetland plant waste to typical plasticizer.The findings are useful for producing designed biochars from different biomass wastes for plasticizer pollution control.
基金grateful to the Ministry of Education,Bangladesh for funding the current work with a project(No.LS2018770)the financial support for chemical analysis provided by Spanish Ministry of Science,Innovation and Universities,Spain and the European Regional Development Fund from the European Union(EU FEDER)(No.RTI2018-099417-B-I00)thankful for receiving a fund from the Kubota Consultancy,The Netherlands(No.3710473400-2).
文摘Biochar is considered a potential technology to enhance chemical fertilizer use efficiency through intensification of the interactions between nutrients and the functional groups on biochar surfaces.However,little is known about how the application of activated biochars mixed with urea influences nitrogen(N)mineralization and crop performance in paddy fields.Here,a sawdust-derived fresh biochar(FBC)(ca.400℃)was activated chemically with 15%hydrogen peroxide and biologically with a nutrient solution mixed with a soil inoculum to obtain a chemically activated biochar(CBC)and a biologically activated biochar(BBC),respectively.The chemical and surface properties of FBC,CBC,and BBC were evaluated using spectroscopic methods,i.e.,Fourier transform infrared spectroscopy and 13C nuclear magnetic resonance,and potentiometric charge determination.The N retention capacity of biochars and their interaction with urea hydrolysis were examined in a laboratory incubation experiment.Additionally,a field experiment was carried out in a paddy field with the biochars unmixed or mixed with urea at a 1:1 ratio.Our results showed that negative surface functional groups and negative charges were increased on both activated biochars,especially CBC.Both activated biochars contributed to a significant reduction in urea-biochar suspension pH and increased N retention in the incubation experiment.Despite the enhanced surface properties of the activated biochars,no similar increases in rice biomass and grain yield were observed for these biochars in the field experiment.However,rice biomass,grain yield,apparent N use efficiency,and agronomic N use efficiency were significantly higher with the application of the three biochars compared to no-biochar application.Altogether,the results indicate that the application of urea mixed with biochar could enhance crop performance,especially in the case of activated biochar,which would enhance N retention in the soil,reducing N loss.
基金the financial supports by the National Natural Science Foundation for Young Scientists of China(No.42007142)the Guangdong Basic and Applied Basic Research Foundation(No.2019A1515110927)the Key Scientific and Technological Project of Foshan City(No.2120001008392).
文摘Municipal wastewater sludge can be pyrolyzed as biochars to better use nutrients and stabilize carbon compared with other typical technologies,such as landfill and incineration.However,sludge-derived biochars might contain large amounts of potentially toxic elements(PTEs),such as Zn,Cu,Cr,Ni,Pb,and As.The stability of PTEs in biochars might be improved by higher pyrolytic temperatures,which can be further improved by different modifications.Herein,PO4-modification at 300°C and Cl-modification at 700°C were carried out,respectively,to enhance the stability of PTEs.Various leaching tests have been performed to assess the stability of PTEs in biochars,including the synthetic precipitation leaching procedure(SPLP),toxicity characteristic leaching procedure(TCLP),diethylenetriamine pentaacetate(DTPA)extraction,and in vitro simple bioaccessibility extraction test(SBET).The morphological structure,elemental mapping,and mineral formation of the pristine and modified biochars were studied by scanning electron microscopy–energy-dispersive X-ray spectroscopy(SEM–EDS)and X-ray diffraction(XRD).Our results suggested that the leachability,mobility,plant-availability,and bioaccessibility of most PTEs were decreased by pyrolysis,yet the total contents of PTEs were elevated,especially at 700°C.Generally,modification by phosphates and MgCl2 enhanced the stability of PTEs in biochars.Nevertheless,it should be noted that higher bioaccessibility of PTEs was observed in biochars of P-modification than Cl-modification,which is associated with the dissolution of phosphate precipitates under acidic conditions(pH<2).Additionally,Cl-modification leads to higher plant-available Zn and Cu and bioaccessible Zn compared with the unmodified biochar produced at 700°C.
基金Fundamental Research Funds of Research Institute of Chemical Industry of Forest Products,CAF(CAFYBB2019SY031)National Key R&D Program(No.2019YFB1503804).
文摘The structural reconstruction mechanism of lignin and cellulose-derived biochars during direct graphitization under ultra-high temperatures was intensively investigated.It was demonstrated that cellulose-derived char was almost composed of carbon microcrystallites,whereas lignin-derived char reserved some of its skeleton structures,and such structural difference played a vital role in the morphology of formed graphitic layers.The results illustrated that the graphitized lignin-derived sample under 2800℃had graphitic degree of 89.53%,interlayer spacing of 0.3363 nm and electronic conductivity of 104.6 S cm^(−1),while cellulose-derived sample had graphitic degree of 76.74%,layer distance of 0.3374 nm,and electronic conductivity of only 48.8 S cm^(−1).Combined with the results of structural analysis of the chars derived from lignin and cellulose,it was inferred that the stable and aromatic ring containing skeleton structure in lignin was beneficial to the ring-enlarging reconstruction and the formation of large areas of continuous graphitic layers during graphitizing process,leading to high electronic conductivity.Meanwhile,the interwoven microcrystallites in cellulose-derived char strongly restricted the expanding of continuous lamellar graphitic areas even at such ultra-high temperature,causing the formation of turbostratic structure with numerous structural defects as well,and finally resulting in relatively lower electronic conductivity.This work is expected to provide theoretical guidance for preparing high-performance functional carbon materials from lignocellulosic biomass.
基金supported by Higher Education Commission(HEC)of Pakistan through the national research program for universities(No.NRPU-7984).
文摘Agricultural wastes are environmental hazards,as these wastes can catch fire,resulting in the loss of human and animal lives and properties.Alternatively,the wastes are dumped in large spaces,which are already limited.Cementitious composites are quasi-brittle and develop cracks at the micro and nano level,which affect their strength,durability,and esthetics.Transforming agricultural wastes to biochar and using it as fibers in cementitious materials for crack arresting and enhancing fracture toughness is an environment-friendly approach.In this research,nano to microscale carbonaceous inert fibers(biochar)of millet and maize were prepared through pyrolysis followed by ball milling.The X-ray spectroscopy(EDX)revealed that 82.08%and 86.89%of the carbon content was retained in millet and maize,respectively.The scanning electron microscope(SEM)confirmed the presence of angular,flaky,and needle-like particles in the carbonaceous inerts,which may enhance the strength and the fracture response of the cementitious materials.These inerts were added individually to mortar specimens at dosage levels of 0,0.025%,0.05%,0.08%,0.2%and 1%by mass of cement.The dispersion of the synthesized nano inerts was ensured by UV–VIS spectroscopy.The compressive strength,flexural strength,porosity,and fracture toughness of cement mortar were evaluated.The carbonized nano intrusions reduced the porosity and density of the mortar specimens.The minimum porosity was noted with 1%and 0.08%dosages of millet and maize,respectively,whereas the minimum density was observed at 1%dosage for both.An increase in compressive and flexural strengths was also noticed.The compressive strength increased by 32%and 28%with 0.2%and 0.5%millet and maize,respectively.An increase of 168%and 114%in fracture toughness was noticed at optimized dosages of 0.5%and 1%of maize and millet,respectively.It is concluded that the addition of carbonaceous inert fibers of millet and maize resulted in light-weight porous mortars with enhanced strength and fracture toughness.The fracture toughness increases with dosage as the nanoparticles enhance the tortuosity.
基金the Natural Science Foundation of China,grant no.32071317
文摘The realization of a stable lithium-metal free(LiMF)sulfur battery based on amorphous carbon anode and lithium sulfide(Li_(2)S)cathode is here reported.In particular,a biomass waste originating full-cell combining a carbonized brewer's spent grain(CBSG)biochar anode with a Li_(2)S-graphene composite cathode(Li_(2)S70Gr30)is proposed.This design is particularly attractive for applying a cost-effective,high performance,environment friendly,and safe anode material,as an alternative to standard graphite and metallic lithium in emerging battery technologies.The anodic and cathodic materials are characterized in terms of structure,morphology and composition through X-ray diffraction,scanning and transmission electron microscopy,X-ray photoelectron and Raman spectroscopies.Furthermore,an electrochemical characterization comprising galvanostatic cycling,rate capability and cyclic voltammetry tests were carried out both in half-cell and full-cell configurations.The systematic investigation reveals that unlike graphite,the biochar electrode displays good compatibility with the electrolyte typically employed in sulfur batteries.The CBSG/Li_(2)S70Gr30 full-cell demonstrates an initial charge and discharge capacities of 726 and 537 mAh g^(-1),respectively,at 0.05C with a coulombic efficiency of 74%.Moreover,it discloses a reversible capacity of 330 mAh g^(-1)(0.1 C)after over 300 cycles.Based on these achievements,the CBSG/Li_(2)S70Gr30 battery system can be considered as a promising energy storage solution for electric vehicles(EVs),especially when taking into account its easy scalability to an industrial level.
基金gratefully acknowledge the financial support for this research from the National Natural Science Foundation of China(Grant No.:21978047,21776046)the Six Talent Climax Foundation of Jiangsu(Grant No.:XCL-079).
文摘A novel photo-catalytic system composed of N-doped biochars(NBCs),MnFe_(2)O_(4) and sulfite activation under ultraviolet(NBCs/MnFe_(2)O_(4)/sulfite/UV)was constructed to realize the efficient eliminate of tetracycline(TC).As the carrier of MnFe_(2)O_(4),NBCs were synthesized from alfalfa,which has large specific surface area,graphite like structure and hierarchical porous structure.The adsorption isotherm indicated that NBCs/MnFe_(2)O_(4)-2:1 had the best adsorption performance for TC(347.56 mg g^(-1)).Through synergistic adsorption and photocatalysis,the removal rate of TC reached 84%,which was significantly higher than that of MnFe_(2)O_(4).Electrochemical impedance spectroscopy(EIS)and Photoluminescence(PL)characterization results showed that the introduction of NBCs improved the separation efficiency of photogenerated electron and hole pairs and enhanced the photocatalytic performance.Moreover,the adsorption,degradation mechanism and degradation path of TC by the catalyst were systematically analyzed by coupling HPLC–MS measurement with the theoretical calculation.Considering the advantages of excellent degradation performance,low cost,easy separation and environmental friendliness of NBCs/MnFe_(2)O_(4),this work was expected to provide a new path for the practical application of biochar.
基金supported by the National Natural Science Foundation of China(No.51663019)the Natural Science Foundation of the Inner Mongolia Autonomous Region(No.2019JQ03)the Program for National Undergraduate Innovation and Entrepreneurship Training(Nos.201911709005 and 201911709006).
文摘Disposal of the pollutants arising from farming cattle and other livestock threatens the environment and public safety in diverse ways.Herein,we report on the synthesis of engineered biochars using cow dung as raw material,and investigating these biochars as antibacterial agents for water decontamination.By coating the biochars with N-halamine polymer and loading them with active chlorine (i.e.,Cl+),we were able to regulate them on demand by tuning the polymer coating and bleaching conditions.The obtained N-halamine-modified biochars were found to be extremely potent against Escherichia coli and Staphylococcus aureus.We also investigated the possibility of using these N-halamine-modified biochars for bacterial decontamination in real-world applications.Our findings indicated that a homemade filter column packed with N-halamine-modified biochars removed pathogenic bacteria from mining sewage,dairy sewage,domestic sewage,and artificial seawater.This proposed strategy could indicate a new way for utilizing livestock pollutants to create on-demand decontaminants.
文摘Feedstock sources and pyrolysis temperatures affect the physicochemical and morphological properties of biochars.We evaluated biochars derived from switchgrass(SGB)and poultry litter(PLB)pyrolyzed at 350℃(SGB350,PLB350)and 700℃(SGB700,PLB700)to identify their potential ability in improving soil health.Except for SGB350,the pH of biochars was high(>10.0)and can be used as an amendment in acid soils.PLB700 had higher mineral content and nutrient availability due to its higher ash content(tenfold higher)and electrical conductivity.Surface functional groups responsible for metal retention were evidenced in all biochars.Cation exchange capacity(CEC),specific surface area(SSA),and microporosity more than doubled by increasing pyrolysis temperature from 350 to 700℃.The pH-buffering capacity measured through acid titration curve was better than that calculated with acid/alkali additions.Biochars pyrolyzed at 700℃ have much higher pH,CEC,SSA,and stronger buffering capacity,and thus are more promising to improve soil health and reduce contaminant bioavailability.
基金the support of the National Environment and Energy International Science and Technology Cooperation Base,the Beijing Science and Technology Program(D141100001214003)the National Key Research and Development Program of China(2016YFD0501402)National Key Research and Development Plan(2016YFE0115600).
文摘In China,substantial agricultural and garden wastes are burned yearly.This practice not only wastes resources but also pollutes air.Corn straw and poplar leaves are typical agricultural and garden waste in China.In this study,corn straw and poplar leaves were used to prepare biochars with different pyrolysis temperatures(250℃,350℃,450℃,550℃and 650℃)and were labeled as CC(corn straw)and LC(poplar leaves),respectively.The biochars were characterized through elemental analysis,Brunauer-Emmett-Teller surface area analysis,scanning electron microscopy and Fourier transform infrared spectroscopy.Yield,ash content and biochar pH were also measured.Results showed that the two biochars possessed some similar characteristics with increasing pyrolysis temperature.These attributes included increased carbon content,biochar hydrophobicity,alkaline pH;decreased hydrogen and oxygen contents and polar functional group content;and enlarged surface area.The biochars also displayed some different characteristics,such as the obviously larger surface area of CC than that of LC at high pyrolysis temperatures and the regular holes of CC and irregular and disordered holes of LC.When biochars CC-650 and LC-650 were used as soil conditioners,the soil pH increased by 0.3 and 0.4 units,respectively,and the soil cation exchange capacity increased by 12.7%and 21.5%,respectively,with respect to those of the blank controls.
基金supported by the Special Research Fund(BOF23PD03,P.Salimi)the Research Foundation Flanders(FWO SB-1S92022N,W.Vercruysse).
文摘Lithium-sulfur batteries are emerging as sustainable replacements for current lithium-ion batteries.The commercial viability of this novel type of battery is still under debate due to the extensive use of highly reactive lithium-metal anodes and the complex electrochemistry of the sulfur cathode.In this research,a novel sulfur-based battery has been proposed that eliminates the need for metallic lithium anodes and other critical raw materials like cobalt and graphite,replacing them with biomass-derived materials.This approach presents numerous benefits,encompassing ample availability,cost-effectiveness,safety,and environmental friendliness.In particular,two types of biochar-based anode electrodes(non-activated and activated biochar)derived from spent common ivy have been investigated as alternatives to metallic lithium.We compared their structural and electrochemical properties,both of which exhibited good compatibility with the typical electrolytes used in sulfur batteries.Surprisingly,while steam activation results in an increased specific surface area,the non-activated ivy biochar demonstrates better performance than the activated biochar,achieving a stable capacity of 400 mA h g^(−1)at 0.1 A g^(−1)and a long lifespan(>400 cycles at 0.5 A g^(−1)).Our results demonstrate that the presence of heteroatoms,such as oxygen and nitrogen positively affects the capacity and cycling performance of the electrodes.This led to increased d-spacing in the graphitic layer,a strong interaction with the solid electrolyte interphase layer,and improved ion transportation.Finally,the non-activated biochar was successfully coupled with a sulfur cathode to fabricate lithium-metal-free sulfur batteries,delivering a specific energy density of~600 Wh kg^(−1).
