Zinc-ion batteries(ZIBs)are considered to be one of the most promising candidates to replace lithium-ion batteries(LIBs)due to the high theoretical capacity,low cost and intrinsic safety.However,zinc dendrites,hydroge...Zinc-ion batteries(ZIBs)are considered to be one of the most promising candidates to replace lithium-ion batteries(LIBs)due to the high theoretical capacity,low cost and intrinsic safety.However,zinc dendrites,hydrogen evolution reaction,surface passivation and other side reactions will inevitably occur during the charging and discharging process of Zn anode,which will seriously affect the cycle stability of the battery and hinder its practical application.The etching strategy of Zn anode has attracted wide attention because of its simple operation and broad commercial prospects,and the etched Zn anode can effectively improve its electrochemical performance.However,there is no comprehensive review of the etching strategy of Zn anode.This review first summarizes the challenges faced by Zn anode,then puts forward the etching mechanisms and properties of acid,salt and other etchants.Finally,based on the above discussion,the challenges and opportunities of Zn anode etching strategy are proposed.展开更多
Removal of uranium(VI)from nuclear wastewater is urgent due to the global nuclear energy exploitation.This study synthesized novel sponge-like 3D porous materials for enhanced uranium adsorption by combining electrosp...Removal of uranium(VI)from nuclear wastewater is urgent due to the global nuclear energy exploitation.This study synthesized novel sponge-like 3D porous materials for enhanced uranium adsorption by combining electrospinning and fibrous freeze-shaping techniques.The materials possessed an organic-inorganic hybrid architecture based on the electrospun fibers of polyacrylonitrile(PAN)and SiO_(2).As a sup-porting material,the surface of fibrous SiO_(2) could be further functionalized by cyano groups via(3-cyanopropyl)triethoxysilane.All the cyano groups were turned into amidoxime(AO)groups to obtain a amidoxime-functionalized sponge(PAO/SiO_(2)-AO)through the subsequent ami-doximation process.The proposed sponge exhibited enhanced uranium adsorption performance with a high removal capacity of 367.12 mg/g,a large adsorption coefficient of 4.0×10^(4)mL/g,and a high removal efficiency of 97.59%.The UO_(2)^(2+)adsorption kinetics perfectly conformed to the pseudo-second-order reaction.The sorbent also exhibited an excellent selectivity for UO_(2)^(2+) with other interfering metal ions.2023 Hohai University.Production and hosting by Elsevier B.V.展开更多
Electrocatalytic reduction of CO_(2)into high energy-density fuels and value-added chemicals under mild conditions can promote the sustainable cycle of carbon and decrease current energy and environmental problems.Con...Electrocatalytic reduction of CO_(2)into high energy-density fuels and value-added chemicals under mild conditions can promote the sustainable cycle of carbon and decrease current energy and environmental problems.Constructing electrocatalyst with high activity,selectivity,stability,and low cost is really matter to realize industrial application of electrocatalytic CO_(2)reduction(ECR).Metal-nitrogen-carbon(M-N-C),especially Ni-N-C,display excellent performance,such as nearly 100%CO selectivity,high current density,outstanding tolerance,etc.,which is considered to possess broad application prospects.Based on the current research status,starting from the mechanism of ECR and the existence form of Ni active species,the latest research progress of Ni-N-C electrocatalysts in CO_(2)electroreduction is systematically summarized.An overview is emphatically interpreted on the regulatory strategies for activity optimization over Ni-N-C,including N coordination modulation,vacancy defects construction,morphology design,surface modification,heteroatom activation,and bimetallic cooperation.Finally,some urgent problems and future prospects on designing Ni-N-C catalysts for ECR are discussed.This review aims to provide the guidance for the design and development of Ni-N-C catalysts with practical application.展开更多
Along with the popularity of environmental protection concepts, the environmental treatment of water pollution attracts widespread attention, among which, the research on Bi-based semiconductor photocatalytic degradat...Along with the popularity of environmental protection concepts, the environmental treatment of water pollution attracts widespread attention, among which, the research on Bi-based semiconductor photocatalytic degradation technology has made great progress. However, the development of such bismuth-based composites still remains a challenging task due to difficult recovery and low catalytic efficiency. Herein, a novel CC/BiPO4</sub>/Bi2</sub>WO6</sub> composite was successfully synthesized through two-step hydrothermal method using activated flexible carbon cloth as a substrate. The results of the photocatalytic degradation experiments showed that the obtained CC/BiPO<sub>4</sub>/Bi<sub>2</sub>WO<sub>6</sub> composites can degrade 92.1% RhB in 60 min under UV-visible light irradiation, which was much higher than that of unloaded BiPO4</sub> (24.4%) and BiPO4</sub>/Bi2</sub>WO6</sub> (52.9%), exhibiting a better adsorption-photocatalytic degradation performance than BiPO4</sub> and BiPO4</sub>/Bi2</sub>WO6</sub>. Photoluminescence spectra indicated that the improved photocatalytic activity was due to the more effective inhibition of photogenerated carrier complexation. Furthermore, the radical capture experiments confirmed that h<sup>+</sup>, ·OH and O<sub>2</sub>-</sup> were the main active substances in the photocatalytic degradation process of RhB by the CC/BiPO4</sub>/Bi2</sub>WO6</sub> composites. More importantly, the prepared CC/BiPO4</sub>/Bi2</sub>WO6</sub> composite had a simple separation process and good recycling stability, and its photocatalytic degradation efficiency can still reach 53.3% after six cycles of RhB degradation. .展开更多
Although the internal electric field(IEF)of photocatalysts is acknowledged as a potent driving force for photocharge separation,modulating the IEF intensity to achieve enhanced photocatalytic performances remains a ch...Although the internal electric field(IEF)of photocatalysts is acknowledged as a potent driving force for photocharge separation,modulating the IEF intensity to achieve enhanced photocatalytic performances remains a challenge.Herein,cuprous sulfide nanosheets with different Cu vacancy concentration were employed to study IEF modulation and corresponding direct charge transfer.Among the samples,Cu_(1.8)S nanosheets possessed intensified IEF intensity compared with those of Cu_(2)S and Cu_(1.95)S nanosheets,suggesting that an enhanced IEF intensity could be achieved by introducing more Cu vacancies.This intensified IEF of Cu_(1.8)S nanosheets induced numerous photogenerated electrons to migrate to its surface,and the dissociative electrons were then captured by Cu vacancies,resulting in efficient charge separation spatially.In addition,the Cu vacancies on Cu_(1.8)S nanosheets accumulated electrons as active sites to lower the energy barrier of rate-determining step of CO_(2)photoreduction,leading to the selective conversion of CO_(2)to CO.Herein,the manipulation of IEF intensity through Cu vacancy concentration regulation of cuprous sulfide photocatalysts for efficient charge separation has been discussed,providing a scientific strategy to rationally improve photocata lytic performances for solar energy conversion.展开更多
Electrochemical energy storage and conversion techniques that exhibit the merits such as high energy density,rapid response kinetics,economical maintenance requirements and expedient installation procedures will hold ...Electrochemical energy storage and conversion techniques that exhibit the merits such as high energy density,rapid response kinetics,economical maintenance requirements and expedient installation procedures will hold a pivotal role in the forthcoming energy storage technologies revolution.In recent years,aqueous zinc-ion batteries(AZIBs)have garnered substantial attention as a compelling candidate for large-scale energy storage systems,primarily attributable to their advantageous featu res encompassing cost-effectiveness,environmental sustainability,and robust safety profiles.Currently,one of the primary factors hindering the further development of AZIBs originates from the challenge of cathode materials.Specifically,the three mainstream types of mainstream cathode materials,in terms of manganese-based compounds,vanadium-based compounds and Prussian blue analogues,surfer from the dissolution of Mn~(2+),in the low discharge voltage,and the low specific capacity,respectively.Several strategies have been developed to compensation the above intrinsic defects for these cathode materials,including the ionic doping,defect engineering,and materials match.Accordingly,this review first provides a systematic summarization of the zinc storage mechanism in AZIBs,following by the inherent merit and demerit of three kind of cathode materials during zinc storage analyzed from their structure characteristic,and then the recent development of critical strategies towards the intrinsic insufficiency of these cathode materials.In this review,the methodologies aimed at enhancing the efficacy of manganese-based and vanadium-based compounds are emphasis emphasized.Additionally,the article outlines the future prospective directions as well as strategic proposal for cathode materials in AZIBs.展开更多
The effects of chromium on the corrosion and the electrochemical behaviors of ultra high strength steels were studied by the salt spray test and electrochemical methods. The results show that ultra high strength steel...The effects of chromium on the corrosion and the electrochemical behaviors of ultra high strength steels were studied by the salt spray test and electrochemical methods. The results show that ultra high strength steels remain martensite structures and have anodic dissolution characteristic with an increase of chromium content. There is no typical passive region on the polarization curves of an ultra high strength stainless steel, AerMet 100 steel, and 300M steel. However, chromium improves the corrosion resistance of the stainless steel remarkably. It has the slowest corrosion rate in the salt spray test, one order of magnitude less than that of AerMet 100 and 300M steels. With the increase of chromium content, the polarization resistance becomes larger, the corrosion potential shifts towards the positive direction with a value of 545 mV, and the corrosion current density decreases in electrochemical measures in 3.5wt% NaCl solutions. Because of the higher content of chromium, the ultra high strength stainless steel has a better corrosion resistance than AerMet 100 and 300M steels.展开更多
Visible-light-responsive ternary metal tungstate(MWO_4) photocatalysts are being increasingly investigated for energy conversion and environmental purification applications owing to their striking features, including ...Visible-light-responsive ternary metal tungstate(MWO_4) photocatalysts are being increasingly investigated for energy conversion and environmental purification applications owing to their striking features, including low cost,eco-friendliness, and high stability under acidic and oxidative conditions. However, rapid recombination of photoinduced electron–hole pairs and a narrow light response range to the solar spectrum lead to low photocatalytic activity of MWO_4-based materials, thus significantly hampering their wide usage in practice. To enable their widespread practical usage, significant efforts have been devoted, by developing new concepts and innovative strategies. In this review, we aim to provide an integrated overview of the fundamentals and recent progress of MWO_4-based photocatalysts. Furthermore, different strategies, including morphological control, surface modification, heteroatom doping, and heterojunction fabrication, which are employed to promote the photocatalyticactivities of MWO_4-based materials, are systematically summarized and discussed. Finally, existing challenges and a future perspective are also provided to shed light on the development of highly efficient MWO_4-based photocatalysts.展开更多
The development of a convenient methodology for synthesizing the hierarchically porous aerogels comprising metal–organic frameworks(MOFs)and graphene oxide(GO)building blocks that exhibit an ultralow density and unif...The development of a convenient methodology for synthesizing the hierarchically porous aerogels comprising metal–organic frameworks(MOFs)and graphene oxide(GO)building blocks that exhibit an ultralow density and uniformly distributed MOFs on GO sheets is important for various applications.Herein,we report a facile route for synthesizing MOF/reduced GO(rGO)aerogels based on the gelation of GO,which is directly initiated using MOF crystals.Free metal ions exposed on the surface of MIL-88A nanorods act as linkers that bind GO nanosheets to a three-dimensional porous network via metal–oxygen covalent or electrostatic interactions.The MOF/rGOderived magnetic and dielectric aerogels Fe_(3)O_(4)@C/rGO and Ni-doped Fe_(3)O_(4)@C/rGO show notable microwave absorption(MA)performance,simultaneously achieving strong absorption and broad bandwidth at low thickness of 2.5(-58.1 dB and 6.48 GHz)and 2.8 mm(-46.2 dB and 7.92 GHz)with ultralow filling contents of 0.7 and 0.6 wt%,respectively.The microwave attenuation ability of the prepared aerogels is further confirmed via a radar cross-sectional simulation,which is attributed to the synergistic effects of their hierarchically porous structures and heterointerface engineering.This work provides an effective pathway for fabricating hierarchically porous MOF/rGO hybrid aerogels and offers magnetic and dielectric aerogels for ultralight MA.展开更多
A novel compound of 9-[3-oxo-1-（4-bromopheny）-3-phenypropyl]fluorine （3） was synthesized via nucleophilic addition reaction under solvent-free condition. Its structure was determined by IR, 1H NMR, MS, elemental a...A novel compound of 9-[3-oxo-1-（4-bromopheny）-3-phenypropyl]fluorine （3） was synthesized via nucleophilic addition reaction under solvent-free condition. Its structure was determined by IR, 1H NMR, MS, elemental analysis and X-ray diffraction. The crystal of the new compound is of triclinic system, space group P-1 with a=9.7919（16）, b=11.0932（18）, c=11.2534（19） , α=76.927（3）, β=67.452（3）, γ=84.895（3）°, V=1099.7（3） 3, Z=2, Dc=1.369 g/cm3, μ=1.886 mm-1, F（000）=464, R=0.0586 and wR=0.1562 for 3145 observed reflections with Ⅰ 2σ（Ⅰ）. π-π Stacking interactions contribute to the stability of the structure.展开更多
Iron hexacyanoferrate(FeHCF)is a promising cathode material for sodium-ion batteries.However,FeHCF always suffers from a poor cycling stability,which is closely related to the abundant vacancy defects in its framework...Iron hexacyanoferrate(FeHCF)is a promising cathode material for sodium-ion batteries.However,FeHCF always suffers from a poor cycling stability,which is closely related to the abundant vacancy defects in its framework.Herein,post-synthetic and in-situ vacancy repairing strategies are proposed for the synthesis of highquality FeHCF in a highly concentrated Na_(4)Fe(CN)_(6) solution.Both the post-synthetic and in-situ vacancy repaired FeHCF products(FeHCF-P and FeHCF-I)show the significant decrease in the number of vacancy defects and the reinforced structure,which can suppress the side reactions and activate the capacity from low-spin Fe in FeHCF.In particular,FeHCF-P delivers a reversible discharge capacity of 131 mAh g^(−1) at 1 C and remains 109 mAh g^(−1) after 500 cycles,with a capacity retention of 83%.FeHCF-I can deliver a high discharge capacity of 158.5 mAh g^(−1) at 1 C.Even at 10 C,the FeHCF-I electrode still maintains a discharge specific capacity of 103 mAh g^(−1) and retains 75% after 800 cycles.This work provides a new vacancy repairing strategy for the solution synthesis of high-quality FeHCF.展开更多
The novel dinuclear copper complex [Cu2（H20）2（DMF）2（L）2] （1, H2L = 5-phenyl- 2H-1,2,3-triazole-4-carboxylic acid, DMF = N,N-dimethyl-formamide） has been synthesized and characterized by X-ray single-crystal di...The novel dinuclear copper complex [Cu2（H20）2（DMF）2（L）2] （1, H2L = 5-phenyl- 2H-1,2,3-triazole-4-carboxylic acid, DMF = N,N-dimethyl-formamide） has been synthesized and characterized by X-ray single-crystal diffraction. The compound crystallizes in triclinic system, space group P1 with a = 9.591, b = 10.508, c = 15.515A,β = 75.11°, V= 1446.2 A3, Z= 2, Mr = 683.62, Dc = 1.570 g/cm3, μ = 1.531 mm^-1, F（000） = 700, the final R = 0.0404 and wR = 0.1130 for 5327 observed reflections with I 〉 2σ（I）. In each unit of the complex, two Cu2＋ ions coordinated with two triazole ligands to form a dimeric [5,6,5] tricyclic structure. The central Cu atom is five-coordinated, and each copper atom shows a square pyramidal geometry. The crystal structure is stabilized by the inversion-related O-H…O hydrogen bond and C-H…O hydrogen bonding interactions to form a layer structure. Fluorescent spectra show an obvious quenching of fluorescence compared with free 1,2,3-triazole ligand. The results of agarose gel electrophoresis indicate that this complex can cleave the plasmid supercoiled DNA within shorter time in the 50-folds excess of ascorbate under physiological conditions, providing a new example in the research for artificial metal nucleic acid enzyme.展开更多
A novel compound of 10-（3,4-dichlorophenymethylidyne）-9,10-dihydrofluorene （C20H12Cl2, Mr = 323.20） was synthesized via Knoevenagel reaction under microwave irradiation （500 w） within short reaction time （8 min...A novel compound of 10-（3,4-dichlorophenymethylidyne）-9,10-dihydrofluorene （C20H12Cl2, Mr = 323.20） was synthesized via Knoevenagel reaction under microwave irradiation （500 w） within short reaction time （8 min）, giving a high yield of product （87%）. Its structure was determined by IR, 1H NMR, MS, elemental analysis and X-ray diffraction. The crystal of the new compound is of monoclinic system, space group P21/c with a = 12.8781（13）, b = 16.5067（16）, c = 7.4656（7）, β = 103.567（2）o, V = 1542.7（3）3, Z = 4, Dc = 1.392 g/cm3, μ = 0.413 mm-1, F（000） = 664, R = 0.0569 and wR = 0.1342 for 3355 observed reflections with I 2σ（I）. The crystal structure involves a conjugated system which shows an olefin structure.展开更多
Photocatalytic solar energy conversion to hydrogen is sustainable and attractive for addressing the global energy and environmental issue. Herein, a novel photocatalytic system (NiS/Ni3S4 cocatalysts modified mesoporo...Photocatalytic solar energy conversion to hydrogen is sustainable and attractive for addressing the global energy and environmental issue. Herein, a novel photocatalytic system (NiS/Ni3S4 cocatalysts modified mesoporous TiO2) with superior photocatalytic hydrogen evolution capability through the synergistic impact of NiS/Ni3S4 (NiSx) cocatalyst and efficient hole scavenger has been demonstrated. The photocatalytic hydrogen evolution of TiO2-NiSx hybrids with the different content of NiSx and upon different organic hole scavengers was both investigated. The hybrid of TiO2 decorated with 3%(mole ratio of Ni^2+) NiSx cocatalyst in methanol solution showed the optimal photocatalytic hydrogen evolution rate of 981.59 μmol h^-1 g^-1 which was about 20 times higher than that of bare mesoporous TiO2. Our results suggested that the boosted hydrogen production performance is attributed to both the improved photoinduced electrons migration between NiS and Ni3S4 in cocatalyst and the high hole captured efficiency by hole scavengers of methanol.展开更多
Sulfate rocks and organic sulfur from sedimentary organic matter are conventionally assumed as the original sulfur sources for hydrogen sulfide （H2S） in oil and gas reservoirs. However, a few recent experiments prel...Sulfate rocks and organic sulfur from sedimentary organic matter are conventionally assumed as the original sulfur sources for hydrogen sulfide （H2S） in oil and gas reservoirs. However, a few recent experiments preliminarily indicate that the association of pyrite and hydrocarbons may also have implications for H2S generation, in which water effects and natural controls on the evolution of pyrite sulfur into OSCs and H2S have not been evaluated. In this study, laboratory experiments were conducted from 200 to 450°C to investigate chemical interactions between pyrite and hydrocarbons under hydrothermal conditions. Based on the experimental results, preliminary mechanism and geochemical implications were tentatively discussed. Results of the experiments showed that decomposition of pyrite produced H2S and thiophenes at as low as 330°C in the presence of water and n-pentane. High concentrations of H2S were generated above 450°C under closed pyrolysis conditions no matter whether there is water in the designed experiments. However, much more organic sulfur compounds （OSCs） were formed in the hydrous pyrolysis than in anhydrous pyrolysis. Generally, most of sulfur liberated from pyrite at elevated temperatures was converted to H2S. Water was beneficial to breakdown of pyrite and to decomposition of alkanes into olefins but not essential to formation of large amounts of H2S, given the main hydrogen source derived from hydrocarbons. In addition, cracking of pyrite in the presence of 1-octene under hydrous conditions was found to proceed at 200°C, producing thiols and alkyl sulfides. Unsaturated hydrocarbons would be more reactive intermediates involved in the breakdown of pyrite than alkanes. The geochemistry of OSCs is actually controlled by various geochemical factors such as thermal maturity and the carbon chain length of the alkanes. This study indicates that the scale of H2S gas generated in deep buried carbonate reservoirs via interactions between pyrite and natural gas should be much smaller than that of thermochemical sulfate reduction （TSR） due to the scarcity of pyrite in carbonate reservoirs and the limited amount of long-chained hydrocarbons in natural gas. Nevertheless, in some cases, OSCs and/or low contents of H2S found in deep buried reservoirs may be associated with the deposited pyrite-bearing rock and organic matters （hydrocarbons）, which still needs further investigation.展开更多
A novel copper（Ⅱ） complex derived from 1,4,7-triazacyclononane[CuL]_2（PF_6）_3×MeCN×H_2 O was synthesized and crystallographically characterized {L = 1,4-bis（2-carbamoylethyl）-7-benzimidazole-2-yl-meth...A novel copper（Ⅱ） complex derived from 1,4,7-triazacyclononane[CuL]_2（PF_6）_3×MeCN×H_2 O was synthesized and crystallographically characterized {L = 1,4-bis（2-carbamoylethyl）-7-benzimidazole-2-yl-methyl-1,4,7-triazacyclononane}. It crystallizes in triclinic, space group P1, with a = 13.2425（13）, b = 14.0807（15）, c = 17.6798（18）, α = 86.296（2）, β = 72.773（2）, γ= 68.905（2）o, V = 2934.5（5）A^3, Z = 2, D_c = 1.611 g/m^3, F（000） = 1456, M_r = 1423.09, m = 0.920 mm^-1. The final R = 0.0671 and wR = 0.1874 for 6501 observed reflections with I 〉 2σ（I）. The structural analysis shows that the complex cation（[CuL]_2^3＋） was formed by two complex cations, namely（[CuL^3]^2＋） and [CuL_（-H）~3]~＋） through a hydrogen bond. In each complex cation, the Cu（Ⅱ） lies in a distorted square pyramidal geometry. The redox behavior was studied by cyclic voltammetry（CV） in aqueous solution which indicates a reversible one electron redox reaction. The result of UV absorption, ethidium bromide（EB） fluorescence spectra indicated that the complex binds to CT-DNA in an intercalative mode. Superoxide dismutase（SOD） activity of the complex was determined by photoreduction of NBT, and the value of IC_（50） is 5.22 μmol·L^-1.展开更多
Four ＂picket fence＂ porphyrin atropisomers were respectively synthesized from the four corresponding atropisomers of meso-tetra（o-aminophenyl）porphyrin that had been chromatographed on a column eluted with petrole...Four ＂picket fence＂ porphyrin atropisomers were respectively synthesized from the four corresponding atropisomers of meso-tetra（o-aminophenyl）porphyrin that had been chromatographed on a column eluted with petroleum ether and ethyl acetate. Results show that each atropisomer could be successfully synthesized by controlling the acylation temperature at 0 ℃. They were characterized by 1H NMR, HRMS, IR, UV-Vis and Langmuir-Blodgett（LB） film analyses. Although the results of HRMS, IR, UV-Vis analyses indicate there is no remarkable difference among the atropisomers, the results of the 1H NMR and the mean molecular areas obtained by LB film technique imply that the atropisomers are significantly discrepant. The former shows that the chemical shifts of the methyl and amide protons of each atropisomer are distinct, while the later presents that the different atropisomer molecules can occupy the different surface areas at the air/water interface.展开更多
Bi_(2)O_(3)/BiOI step-scheme(S-scheme) heterojunction photocatalyst was synthesized by green calcination method, its degradation ability of methylene blue was investigated, and the photocatalytic performance of the Bi...Bi_(2)O_(3)/BiOI step-scheme(S-scheme) heterojunction photocatalyst was synthesized by green calcination method, its degradation ability of methylene blue was investigated, and the photocatalytic performance of the Bi_(2)O_(3)/BiOI heterojunction, Bi_(2)O_(3) and BiOI was compared. The structure and morphology of the samples were characterized by X-ray diffraction(XRD), field emission scanning electron microscopy(FESEM), and UV-vis diffuse reflection spectrum (UV-vis DRS). The degradation rate of methylene blue was analysised by spectrophotometry, and the calculation result showed that the degradation rate of methylene blue was 97.8% in 150 minutes. The first order kinetic rate constant of 10%Bi_(2)O_(3)/BiOI is 0.021 8 min^(-1), which are2.37 and 2.68 times of BiOI(0.009 18 min^(-1)) and Bi_(2)O_(3) (0.008 03 min^(-1)) respectively. The calculation result shows that the work function of Bi_(2)O_(3) and BiOI are 3.0 e V and 6.0 e V, respectively, by density functional theory(DFT). When this S-scheme heterojunction is used as a photocatalyst, the weaker electrons in the conduction band of BiOI will be combined with the weaker holes in the Bi_(2)O_(3) valence band under combined effect with built-in electric field and band bending, which will retain stronger photoelectrons and holes between Bi_(2)O_(3) and BiOI. This may be the internal reason for the efficient degradation of tetracycline by Bi_(2)O_(3)/BiOI S-scheme heterostructures.展开更多
Tb（Ⅲ ）-trimesic acid （TMA） luminescent complexes were synthesized in the polyvinylpyrrolidone （PVP） matrix. The elemental analysis, inductively coupled plasma-atomic emission spectroscopy （ICP-AES） and fourie...Tb（Ⅲ ）-trimesic acid （TMA） luminescent complexes were synthesized in the polyvinylpyrrolidone （PVP） matrix. The elemental analysis, inductively coupled plasma-atomic emission spectroscopy （ICP-AES） and fourier-transform infrared spectroscopy （FT-IR） indicated that its chemical constitution is PVP/Tb（MTA）· 4H2O. The XRD patterns showed that the complex is a new kind of crystal. The TEM image indicates that the complex is rod shaped. The rod diameter is about 200 nm, and the length ranges from hundred of nanometer to a few micrometers. In addition, the dispersity is better. TG-DTA curves indicate that the complex is thermally stable before 463℃. Photoluminescence analysis indicates that the complex emits Tb^3＋ characteristic luminescence under ultraviolet excitation.展开更多
Crystalline metal-organic framework cobalt （II） benzenetricarboxylate C%（BTC）2·12H2O （MOF-Co） has been prepared using solvothermal method. The reaction of cobalt （II） nitrate and 1,3,5-benzenetriearboxyl...Crystalline metal-organic framework cobalt （II） benzenetricarboxylate C%（BTC）2·12H2O （MOF-Co） has been prepared using solvothermal method. The reaction of cobalt （II） nitrate and 1,3,5-benzenetriearboxylic （BTC） acid in a mixed solution of N,N-dimethylformarnide （DMF）/C2H5OH/H2O （1：1：1, v/v） at low temperature for short reaction times produced this crystalline compound. Compared with traditional hydrothermal method, a mixed solution method for the synthesis of crystalline metal complex was found to be highly efficient. After water molecules were removed from this metal complex, its exposed nodes served as active sites. When this MOF-Co was employed in the oxidation of CO, it showed good catalytic properties causing 100% conversion of CO to CO2 at low temperature of 160 ℃.展开更多
基金supported by the Science and Technology Research Project of the Education Department of Jilin Province (JJKH20230803KJ)。
文摘Zinc-ion batteries(ZIBs)are considered to be one of the most promising candidates to replace lithium-ion batteries(LIBs)due to the high theoretical capacity,low cost and intrinsic safety.However,zinc dendrites,hydrogen evolution reaction,surface passivation and other side reactions will inevitably occur during the charging and discharging process of Zn anode,which will seriously affect the cycle stability of the battery and hinder its practical application.The etching strategy of Zn anode has attracted wide attention because of its simple operation and broad commercial prospects,and the etched Zn anode can effectively improve its electrochemical performance.However,there is no comprehensive review of the etching strategy of Zn anode.This review first summarizes the challenges faced by Zn anode,then puts forward the etching mechanisms and properties of acid,salt and other etchants.Finally,based on the above discussion,the challenges and opportunities of Zn anode etching strategy are proposed.
基金supported by the Opening Project of the Jiangsu Province Engineering Research Center of Agricultural Breeding Pollution Control and Resource(Grant No.2021ABPCR010)the Natural Science Research Project of Jiangsu Higher Education Institutions of China(Grants No.20KJB150035,21KJD610004,and 21KJA530004).
文摘Removal of uranium(VI)from nuclear wastewater is urgent due to the global nuclear energy exploitation.This study synthesized novel sponge-like 3D porous materials for enhanced uranium adsorption by combining electrospinning and fibrous freeze-shaping techniques.The materials possessed an organic-inorganic hybrid architecture based on the electrospun fibers of polyacrylonitrile(PAN)and SiO_(2).As a sup-porting material,the surface of fibrous SiO_(2) could be further functionalized by cyano groups via(3-cyanopropyl)triethoxysilane.All the cyano groups were turned into amidoxime(AO)groups to obtain a amidoxime-functionalized sponge(PAO/SiO_(2)-AO)through the subsequent ami-doximation process.The proposed sponge exhibited enhanced uranium adsorption performance with a high removal capacity of 367.12 mg/g,a large adsorption coefficient of 4.0×10^(4)mL/g,and a high removal efficiency of 97.59%.The UO_(2)^(2+)adsorption kinetics perfectly conformed to the pseudo-second-order reaction.The sorbent also exhibited an excellent selectivity for UO_(2)^(2+) with other interfering metal ions.2023 Hohai University.Production and hosting by Elsevier B.V.
基金financially supported by the National Natural Science Foundation of China(22278380,22108259)China Postdoctoral Science Foundation(2021M692911,2022T150589)
文摘Electrocatalytic reduction of CO_(2)into high energy-density fuels and value-added chemicals under mild conditions can promote the sustainable cycle of carbon and decrease current energy and environmental problems.Constructing electrocatalyst with high activity,selectivity,stability,and low cost is really matter to realize industrial application of electrocatalytic CO_(2)reduction(ECR).Metal-nitrogen-carbon(M-N-C),especially Ni-N-C,display excellent performance,such as nearly 100%CO selectivity,high current density,outstanding tolerance,etc.,which is considered to possess broad application prospects.Based on the current research status,starting from the mechanism of ECR and the existence form of Ni active species,the latest research progress of Ni-N-C electrocatalysts in CO_(2)electroreduction is systematically summarized.An overview is emphatically interpreted on the regulatory strategies for activity optimization over Ni-N-C,including N coordination modulation,vacancy defects construction,morphology design,surface modification,heteroatom activation,and bimetallic cooperation.Finally,some urgent problems and future prospects on designing Ni-N-C catalysts for ECR are discussed.This review aims to provide the guidance for the design and development of Ni-N-C catalysts with practical application.
文摘Along with the popularity of environmental protection concepts, the environmental treatment of water pollution attracts widespread attention, among which, the research on Bi-based semiconductor photocatalytic degradation technology has made great progress. However, the development of such bismuth-based composites still remains a challenging task due to difficult recovery and low catalytic efficiency. Herein, a novel CC/BiPO4</sub>/Bi2</sub>WO6</sub> composite was successfully synthesized through two-step hydrothermal method using activated flexible carbon cloth as a substrate. The results of the photocatalytic degradation experiments showed that the obtained CC/BiPO<sub>4</sub>/Bi<sub>2</sub>WO<sub>6</sub> composites can degrade 92.1% RhB in 60 min under UV-visible light irradiation, which was much higher than that of unloaded BiPO4</sub> (24.4%) and BiPO4</sub>/Bi2</sub>WO6</sub> (52.9%), exhibiting a better adsorption-photocatalytic degradation performance than BiPO4</sub> and BiPO4</sub>/Bi2</sub>WO6</sub>. Photoluminescence spectra indicated that the improved photocatalytic activity was due to the more effective inhibition of photogenerated carrier complexation. Furthermore, the radical capture experiments confirmed that h<sup>+</sup>, ·OH and O<sub>2</sub>-</sup> were the main active substances in the photocatalytic degradation process of RhB by the CC/BiPO4</sub>/Bi2</sub>WO6</sub> composites. More importantly, the prepared CC/BiPO4</sub>/Bi2</sub>WO6</sub> composite had a simple separation process and good recycling stability, and its photocatalytic degradation efficiency can still reach 53.3% after six cycles of RhB degradation. .
基金supported by the National Natural Science Foundation of China(52200123)the Open Project of Key Laboratory of Green Chemical Engineering Process of Ministry of Education(GCP2022007)the Scientific Research and Innovation Team Program of Sichuan University of Science and Engineering(SUSE652A014)。
文摘Although the internal electric field(IEF)of photocatalysts is acknowledged as a potent driving force for photocharge separation,modulating the IEF intensity to achieve enhanced photocatalytic performances remains a challenge.Herein,cuprous sulfide nanosheets with different Cu vacancy concentration were employed to study IEF modulation and corresponding direct charge transfer.Among the samples,Cu_(1.8)S nanosheets possessed intensified IEF intensity compared with those of Cu_(2)S and Cu_(1.95)S nanosheets,suggesting that an enhanced IEF intensity could be achieved by introducing more Cu vacancies.This intensified IEF of Cu_(1.8)S nanosheets induced numerous photogenerated electrons to migrate to its surface,and the dissociative electrons were then captured by Cu vacancies,resulting in efficient charge separation spatially.In addition,the Cu vacancies on Cu_(1.8)S nanosheets accumulated electrons as active sites to lower the energy barrier of rate-determining step of CO_(2)photoreduction,leading to the selective conversion of CO_(2)to CO.Herein,the manipulation of IEF intensity through Cu vacancy concentration regulation of cuprous sulfide photocatalysts for efficient charge separation has been discussed,providing a scientific strategy to rationally improve photocata lytic performances for solar energy conversion.
基金supported by the Science and Technology Development Planning of Jilin Province (20240101153JC)the Department of Education of Jilin Province (JJKH20240905KJ)the National Natural Science Foundation of China (21972133)。
文摘Electrochemical energy storage and conversion techniques that exhibit the merits such as high energy density,rapid response kinetics,economical maintenance requirements and expedient installation procedures will hold a pivotal role in the forthcoming energy storage technologies revolution.In recent years,aqueous zinc-ion batteries(AZIBs)have garnered substantial attention as a compelling candidate for large-scale energy storage systems,primarily attributable to their advantageous featu res encompassing cost-effectiveness,environmental sustainability,and robust safety profiles.Currently,one of the primary factors hindering the further development of AZIBs originates from the challenge of cathode materials.Specifically,the three mainstream types of mainstream cathode materials,in terms of manganese-based compounds,vanadium-based compounds and Prussian blue analogues,surfer from the dissolution of Mn~(2+),in the low discharge voltage,and the low specific capacity,respectively.Several strategies have been developed to compensation the above intrinsic defects for these cathode materials,including the ionic doping,defect engineering,and materials match.Accordingly,this review first provides a systematic summarization of the zinc storage mechanism in AZIBs,following by the inherent merit and demerit of three kind of cathode materials during zinc storage analyzed from their structure characteristic,and then the recent development of critical strategies towards the intrinsic insufficiency of these cathode materials.In this review,the methodologies aimed at enhancing the efficacy of manganese-based and vanadium-based compounds are emphasis emphasized.Additionally,the article outlines the future prospective directions as well as strategic proposal for cathode materials in AZIBs.
基金supported by the National Science and Technology Infrastructure Platforms Construction Projects of China (Grant No2005DKA10400)the National Science Foundation of China (No50871021)
文摘The effects of chromium on the corrosion and the electrochemical behaviors of ultra high strength steels were studied by the salt spray test and electrochemical methods. The results show that ultra high strength steels remain martensite structures and have anodic dissolution characteristic with an increase of chromium content. There is no typical passive region on the polarization curves of an ultra high strength stainless steel, AerMet 100 steel, and 300M steel. However, chromium improves the corrosion resistance of the stainless steel remarkably. It has the slowest corrosion rate in the salt spray test, one order of magnitude less than that of AerMet 100 and 300M steels. With the increase of chromium content, the polarization resistance becomes larger, the corrosion potential shifts towards the positive direction with a value of 545 mV, and the corrosion current density decreases in electrochemical measures in 3.5wt% NaCl solutions. Because of the higher content of chromium, the ultra high strength stainless steel has a better corrosion resistance than AerMet 100 and 300M steels.
基金support of NSFC 51702284Fundamental Research Funds for the Central Universities (112109*172210171)+2 种基金the Startup Foundation for Hundred-Talent Program of Zhejiang University (112100-193820101/001/022)support of the NSFC 21501138the Science Research Foundation of Wuhan Institute of Technology (K201513)
文摘Visible-light-responsive ternary metal tungstate(MWO_4) photocatalysts are being increasingly investigated for energy conversion and environmental purification applications owing to their striking features, including low cost,eco-friendliness, and high stability under acidic and oxidative conditions. However, rapid recombination of photoinduced electron–hole pairs and a narrow light response range to the solar spectrum lead to low photocatalytic activity of MWO_4-based materials, thus significantly hampering their wide usage in practice. To enable their widespread practical usage, significant efforts have been devoted, by developing new concepts and innovative strategies. In this review, we aim to provide an integrated overview of the fundamentals and recent progress of MWO_4-based photocatalysts. Furthermore, different strategies, including morphological control, surface modification, heteroatom doping, and heterojunction fabrication, which are employed to promote the photocatalyticactivities of MWO_4-based materials, are systematically summarized and discussed. Finally, existing challenges and a future perspective are also provided to shed light on the development of highly efficient MWO_4-based photocatalysts.
基金the National Natural Science Foundation of China(52102361,62071239)Natural Science Foundation of Jiangsu Province(BK20200827)+1 种基金National Key Laboratory on Electromagnetic Environmental Effects and Electro-optical Engineering(JCKYS2022LD2)the Startup Foundation for Introducing Talent of NUIST。
文摘The development of a convenient methodology for synthesizing the hierarchically porous aerogels comprising metal–organic frameworks(MOFs)and graphene oxide(GO)building blocks that exhibit an ultralow density and uniformly distributed MOFs on GO sheets is important for various applications.Herein,we report a facile route for synthesizing MOF/reduced GO(rGO)aerogels based on the gelation of GO,which is directly initiated using MOF crystals.Free metal ions exposed on the surface of MIL-88A nanorods act as linkers that bind GO nanosheets to a three-dimensional porous network via metal–oxygen covalent or electrostatic interactions.The MOF/rGOderived magnetic and dielectric aerogels Fe_(3)O_(4)@C/rGO and Ni-doped Fe_(3)O_(4)@C/rGO show notable microwave absorption(MA)performance,simultaneously achieving strong absorption and broad bandwidth at low thickness of 2.5(-58.1 dB and 6.48 GHz)and 2.8 mm(-46.2 dB and 7.92 GHz)with ultralow filling contents of 0.7 and 0.6 wt%,respectively.The microwave attenuation ability of the prepared aerogels is further confirmed via a radar cross-sectional simulation,which is attributed to the synergistic effects of their hierarchically porous structures and heterointerface engineering.This work provides an effective pathway for fabricating hierarchically porous MOF/rGO hybrid aerogels and offers magnetic and dielectric aerogels for ultralight MA.
基金Supported by the Team Research for Excellent Mid-aged and Young Teachers of Higher Education of Hubei Province (T200707)
文摘A novel compound of 9-[3-oxo-1-（4-bromopheny）-3-phenypropyl]fluorine （3） was synthesized via nucleophilic addition reaction under solvent-free condition. Its structure was determined by IR, 1H NMR, MS, elemental analysis and X-ray diffraction. The crystal of the new compound is of triclinic system, space group P-1 with a=9.7919（16）, b=11.0932（18）, c=11.2534（19） , α=76.927（3）, β=67.452（3）, γ=84.895（3）°, V=1099.7（3） 3, Z=2, Dc=1.369 g/cm3, μ=1.886 mm-1, F（000）=464, R=0.0586 and wR=0.1562 for 3145 observed reflections with Ⅰ 2σ（Ⅰ）. π-π Stacking interactions contribute to the stability of the structure.
基金supported by the projects of the National Key R&D Program of China(2016YFB0100302)the National Natural Science Foundation of China(Grant No.60306011).
文摘Iron hexacyanoferrate(FeHCF)is a promising cathode material for sodium-ion batteries.However,FeHCF always suffers from a poor cycling stability,which is closely related to the abundant vacancy defects in its framework.Herein,post-synthetic and in-situ vacancy repairing strategies are proposed for the synthesis of highquality FeHCF in a highly concentrated Na_(4)Fe(CN)_(6) solution.Both the post-synthetic and in-situ vacancy repaired FeHCF products(FeHCF-P and FeHCF-I)show the significant decrease in the number of vacancy defects and the reinforced structure,which can suppress the side reactions and activate the capacity from low-spin Fe in FeHCF.In particular,FeHCF-P delivers a reversible discharge capacity of 131 mAh g^(−1) at 1 C and remains 109 mAh g^(−1) after 500 cycles,with a capacity retention of 83%.FeHCF-I can deliver a high discharge capacity of 158.5 mAh g^(−1) at 1 C.Even at 10 C,the FeHCF-I electrode still maintains a discharge specific capacity of 103 mAh g^(−1) and retains 75% after 800 cycles.This work provides a new vacancy repairing strategy for the solution synthesis of high-quality FeHCF.
基金supported by the National Natural Science Foundation of China(No.21002076)Wuhan Youth Chenguang Program of Science and Technology(No.201271031374)
文摘The novel dinuclear copper complex [Cu2（H20）2（DMF）2（L）2] （1, H2L = 5-phenyl- 2H-1,2,3-triazole-4-carboxylic acid, DMF = N,N-dimethyl-formamide） has been synthesized and characterized by X-ray single-crystal diffraction. The compound crystallizes in triclinic system, space group P1 with a = 9.591, b = 10.508, c = 15.515A,β = 75.11°, V= 1446.2 A3, Z= 2, Mr = 683.62, Dc = 1.570 g/cm3, μ = 1.531 mm^-1, F（000） = 700, the final R = 0.0404 and wR = 0.1130 for 5327 observed reflections with I 〉 2σ（I）. In each unit of the complex, two Cu2＋ ions coordinated with two triazole ligands to form a dimeric [5,6,5] tricyclic structure. The central Cu atom is five-coordinated, and each copper atom shows a square pyramidal geometry. The crystal structure is stabilized by the inversion-related O-H…O hydrogen bond and C-H…O hydrogen bonding interactions to form a layer structure. Fluorescent spectra show an obvious quenching of fluorescence compared with free 1,2,3-triazole ligand. The results of agarose gel electrophoresis indicate that this complex can cleave the plasmid supercoiled DNA within shorter time in the 50-folds excess of ascorbate under physiological conditions, providing a new example in the research for artificial metal nucleic acid enzyme.
基金Supported by the Team Research for Excellent Mid-aged and Young Teachers of Higher Education of Hubei Province (T201006)
文摘A novel compound of 10-（3,4-dichlorophenymethylidyne）-9,10-dihydrofluorene （C20H12Cl2, Mr = 323.20） was synthesized via Knoevenagel reaction under microwave irradiation （500 w） within short reaction time （8 min）, giving a high yield of product （87%）. Its structure was determined by IR, 1H NMR, MS, elemental analysis and X-ray diffraction. The crystal of the new compound is of monoclinic system, space group P21/c with a = 12.8781（13）, b = 16.5067（16）, c = 7.4656（7）, β = 103.567（2）o, V = 1542.7（3）3, Z = 4, Dc = 1.392 g/cm3, μ = 0.413 mm-1, F（000） = 664, R = 0.0569 and wR = 0.1342 for 3355 observed reflections with I 2σ（I）. The crystal structure involves a conjugated system which shows an olefin structure.
基金the National Natural Science Foundation of China(21501137)the Hubei Natural Science Foundation for financial support(2018CFB680)Support from the Australian Research Council(ARC)through ARC Discovery projects(DP130102699,DP 130102274,DP160102627)
文摘Photocatalytic solar energy conversion to hydrogen is sustainable and attractive for addressing the global energy and environmental issue. Herein, a novel photocatalytic system (NiS/Ni3S4 cocatalysts modified mesoporous TiO2) with superior photocatalytic hydrogen evolution capability through the synergistic impact of NiS/Ni3S4 (NiSx) cocatalyst and efficient hole scavenger has been demonstrated. The photocatalytic hydrogen evolution of TiO2-NiSx hybrids with the different content of NiSx and upon different organic hole scavengers was both investigated. The hybrid of TiO2 decorated with 3%(mole ratio of Ni^2+) NiSx cocatalyst in methanol solution showed the optimal photocatalytic hydrogen evolution rate of 981.59 μmol h^-1 g^-1 which was about 20 times higher than that of bare mesoporous TiO2. Our results suggested that the boosted hydrogen production performance is attributed to both the improved photoinduced electrons migration between NiS and Ni3S4 in cocatalyst and the high hole captured efficiency by hole scavengers of methanol.
基金the National Natural Science Foundations of China(No.41472095 and No.40902034)the Foundation of State Key Laboratory of Petroleum Resources and Prospecting,China University of Petroleum,Beijing(No.PRP/open-1508)PetroChina Innovation Foundation(No.2012D-5006-0104)
文摘Sulfate rocks and organic sulfur from sedimentary organic matter are conventionally assumed as the original sulfur sources for hydrogen sulfide （H2S） in oil and gas reservoirs. However, a few recent experiments preliminarily indicate that the association of pyrite and hydrocarbons may also have implications for H2S generation, in which water effects and natural controls on the evolution of pyrite sulfur into OSCs and H2S have not been evaluated. In this study, laboratory experiments were conducted from 200 to 450°C to investigate chemical interactions between pyrite and hydrocarbons under hydrothermal conditions. Based on the experimental results, preliminary mechanism and geochemical implications were tentatively discussed. Results of the experiments showed that decomposition of pyrite produced H2S and thiophenes at as low as 330°C in the presence of water and n-pentane. High concentrations of H2S were generated above 450°C under closed pyrolysis conditions no matter whether there is water in the designed experiments. However, much more organic sulfur compounds （OSCs） were formed in the hydrous pyrolysis than in anhydrous pyrolysis. Generally, most of sulfur liberated from pyrite at elevated temperatures was converted to H2S. Water was beneficial to breakdown of pyrite and to decomposition of alkanes into olefins but not essential to formation of large amounts of H2S, given the main hydrogen source derived from hydrocarbons. In addition, cracking of pyrite in the presence of 1-octene under hydrous conditions was found to proceed at 200°C, producing thiols and alkyl sulfides. Unsaturated hydrocarbons would be more reactive intermediates involved in the breakdown of pyrite than alkanes. The geochemistry of OSCs is actually controlled by various geochemical factors such as thermal maturity and the carbon chain length of the alkanes. This study indicates that the scale of H2S gas generated in deep buried carbonate reservoirs via interactions between pyrite and natural gas should be much smaller than that of thermochemical sulfate reduction （TSR） due to the scarcity of pyrite in carbonate reservoirs and the limited amount of long-chained hydrocarbons in natural gas. Nevertheless, in some cases, OSCs and/or low contents of H2S found in deep buried reservoirs may be associated with the deposited pyrite-bearing rock and organic matters （hydrocarbons）, which still needs further investigation.
基金supported by the Natural Science Foundation of Hubei Province(2014CFB410)
文摘A novel copper（Ⅱ） complex derived from 1,4,7-triazacyclononane[CuL]_2（PF_6）_3×MeCN×H_2 O was synthesized and crystallographically characterized {L = 1,4-bis（2-carbamoylethyl）-7-benzimidazole-2-yl-methyl-1,4,7-triazacyclononane}. It crystallizes in triclinic, space group P1, with a = 13.2425（13）, b = 14.0807（15）, c = 17.6798（18）, α = 86.296（2）, β = 72.773（2）, γ= 68.905（2）o, V = 2934.5（5）A^3, Z = 2, D_c = 1.611 g/m^3, F（000） = 1456, M_r = 1423.09, m = 0.920 mm^-1. The final R = 0.0671 and wR = 0.1874 for 6501 observed reflections with I 〉 2σ（I）. The structural analysis shows that the complex cation（[CuL]_2^3＋） was formed by two complex cations, namely（[CuL^3]^2＋） and [CuL_（-H）~3]~＋） through a hydrogen bond. In each complex cation, the Cu（Ⅱ） lies in a distorted square pyramidal geometry. The redox behavior was studied by cyclic voltammetry（CV） in aqueous solution which indicates a reversible one electron redox reaction. The result of UV absorption, ethidium bromide（EB） fluorescence spectra indicated that the complex binds to CT-DNA in an intercalative mode. Superoxide dismutase（SOD） activity of the complex was determined by photoreduction of NBT, and the value of IC_（50） is 5.22 μmol·L^-1.
基金Supported by the National Natural Science Foundation of China(No.20806025)
文摘Four ＂picket fence＂ porphyrin atropisomers were respectively synthesized from the four corresponding atropisomers of meso-tetra（o-aminophenyl）porphyrin that had been chromatographed on a column eluted with petroleum ether and ethyl acetate. Results show that each atropisomer could be successfully synthesized by controlling the acylation temperature at 0 ℃. They were characterized by 1H NMR, HRMS, IR, UV-Vis and Langmuir-Blodgett（LB） film analyses. Although the results of HRMS, IR, UV-Vis analyses indicate there is no remarkable difference among the atropisomers, the results of the 1H NMR and the mean molecular areas obtained by LB film technique imply that the atropisomers are significantly discrepant. The former shows that the chemical shifts of the methyl and amide protons of each atropisomer are distinct, while the later presents that the different atropisomer molecules can occupy the different surface areas at the air/water interface.
基金Funded by National Natural Science Foundation of China (No.21769009)Project of Innovation and Entrepreneurship for College Students in Hubei Minzu University (No.S202010517044)+2 种基金The foundation of Key Laboratory of Green Manufacturing of Super-light Elastomer Materials of State Ethnic Affairs Commission.(Hubei Minzu University)(No.PT092101)The Open Project of Guangxi Key Laboratory of Chemistry and Engineering of Forest Products(No.GXFK1904)Specific Research Project of Guangxi for Research Bases and Talents(No.AD18126005)。
文摘Bi_(2)O_(3)/BiOI step-scheme(S-scheme) heterojunction photocatalyst was synthesized by green calcination method, its degradation ability of methylene blue was investigated, and the photocatalytic performance of the Bi_(2)O_(3)/BiOI heterojunction, Bi_(2)O_(3) and BiOI was compared. The structure and morphology of the samples were characterized by X-ray diffraction(XRD), field emission scanning electron microscopy(FESEM), and UV-vis diffuse reflection spectrum (UV-vis DRS). The degradation rate of methylene blue was analysised by spectrophotometry, and the calculation result showed that the degradation rate of methylene blue was 97.8% in 150 minutes. The first order kinetic rate constant of 10%Bi_(2)O_(3)/BiOI is 0.021 8 min^(-1), which are2.37 and 2.68 times of BiOI(0.009 18 min^(-1)) and Bi_(2)O_(3) (0.008 03 min^(-1)) respectively. The calculation result shows that the work function of Bi_(2)O_(3) and BiOI are 3.0 e V and 6.0 e V, respectively, by density functional theory(DFT). When this S-scheme heterojunction is used as a photocatalyst, the weaker electrons in the conduction band of BiOI will be combined with the weaker holes in the Bi_(2)O_(3) valence band under combined effect with built-in electric field and band bending, which will retain stronger photoelectrons and holes between Bi_(2)O_(3) and BiOI. This may be the internal reason for the efficient degradation of tetracycline by Bi_(2)O_(3)/BiOI S-scheme heterostructures.
基金Project supported bythe Science Fund of Education Office in Jilin Province (200468)
文摘Tb（Ⅲ ）-trimesic acid （TMA） luminescent complexes were synthesized in the polyvinylpyrrolidone （PVP） matrix. The elemental analysis, inductively coupled plasma-atomic emission spectroscopy （ICP-AES） and fourier-transform infrared spectroscopy （FT-IR） indicated that its chemical constitution is PVP/Tb（MTA）· 4H2O. The XRD patterns showed that the complex is a new kind of crystal. The TEM image indicates that the complex is rod shaped. The rod diameter is about 200 nm, and the length ranges from hundred of nanometer to a few micrometers. In addition, the dispersity is better. TG-DTA curves indicate that the complex is thermally stable before 463℃. Photoluminescence analysis indicates that the complex emits Tb^3＋ characteristic luminescence under ultraviolet excitation.
基金Funded by the Natural Science Foundation of Hubei Province,China(No.2011CDA070)Research Fund for the Doctoral Program of Hubei University for Nationalities(No.MY2014B013)
文摘Crystalline metal-organic framework cobalt （II） benzenetricarboxylate C%（BTC）2·12H2O （MOF-Co） has been prepared using solvothermal method. The reaction of cobalt （II） nitrate and 1,3,5-benzenetriearboxylic （BTC） acid in a mixed solution of N,N-dimethylformarnide （DMF）/C2H5OH/H2O （1：1：1, v/v） at low temperature for short reaction times produced this crystalline compound. Compared with traditional hydrothermal method, a mixed solution method for the synthesis of crystalline metal complex was found to be highly efficient. After water molecules were removed from this metal complex, its exposed nodes served as active sites. When this MOF-Co was employed in the oxidation of CO, it showed good catalytic properties causing 100% conversion of CO to CO2 at low temperature of 160 ℃.
