The depolymerization and upgrading of lignin from raw biomass,while keeping cellulose intact is important in biorefinery and various metal-based catalysts have been used in reductive catalytic fractionation,a key meth...The depolymerization and upgrading of lignin from raw biomass,while keeping cellulose intact is important in biorefinery and various metal-based catalysts have been used in reductive catalytic fractionation,a key method in"lignin-first"strategy,Recently,we found that a core-shell structured Co@CoO catalyst with CoO shell as the real active site had excellent performance in the hydrogenolysis of 5-hydromethylfurfural to 2,5-dimethylfuran due to its unique ability to dissociate H_(2)and yield active H^(δ-)species(Xiang et al.,2022).In this work,we report a one-pot depolymerization and upgrading of lignocellulose to alkylcyclohexanols,a flavour precursor,with intact cellulose over this unique core-shell structured catalyst,Co@CoO.Lignin model compounds(β-O-4,4-O-5,α-O-4)were first used to clarify the activity of Co@CoO catalyst.Then,the one-pot conversion of various organosolv lignin(birch,pine and poplar)to alkylcyclohexanols was realized with the mass yield of alkylcyclohexanols up to25.8 wt%from birch lignin under the reaction condition of 210℃,1 MPa H_(2),16 h.Finally,the corresponding woody sawdusts were used as feedstocks and found that the Co@CoO catalyst indeed preferentially depolymerized and upgraded the lignin part and obtained the same alkylcyclohexanols products with the retention of cellulose-rich pulp.The collected alkylcyclohexanols were further esterified to obtain valueadded esters,which can be used as flavors.This work will inspire the design of new efficient metal oxide catalysts in lignin fractionation and depolymerization to high-value-added chemicals with intact cellulose.展开更多
The interface between Au and support has attracted extensive interest because of its unique catalytic ability for hydrogen activation in catalytic hydrogenation/hydrogenolysis reactions.Herein,we create the Au-CoO-OV ...The interface between Au and support has attracted extensive interest because of its unique catalytic ability for hydrogen activation in catalytic hydrogenation/hydrogenolysis reactions.Herein,we create the Au-CoO-OV interface in the 1.0%Au/Co3O4-Rod-250 catalyst,which could dissociate H2 via the heterolytic way to yield rich hydride species and achieve excellent catalytic performance in the hydrogenolysis of biomass-derived 5-hydroxymethylfurfural(HMF)to 2,5-dimethylfuran(DMF).The XRD and HRTEM analyses show that Au nanoparticles are uniformly dispersed on CoO-OV surface and in situ DRIFTS spectra show the enhancement of heterolytic dissociation of hydrogen(signals of Au-D and O-D vibration)compared with bare CoO(Co3O4-Rod-250).This work provides insights for fabricating highly active Au-support catalysts for catalytic hydrogenation/hydrogenolysis reactions.展开更多
Organic cocrystal as an emerging assembly strategy has received increasing attention in constructing multiple functional materials,through continually screening suitable constituent monomers or changing their stoichio...Organic cocrystal as an emerging assembly strategy has received increasing attention in constructing multiple functional materials,through continually screening suitable constituent monomers or changing their stoichiometry ratios.However,the role of molecule configuration in the cocrystal field is rarely explored despite the fascinating potential in regulating the packing mode.In this study,the N,N′-diphenyl-5,10-dihydrophenazine derivatives(DPPs) with the flexible scaffold and different methyl substitutions are selected as the donors bearing various molecular configurations.In a simple collaborative way,a series of cocrystals based on DPPs and OFN(octafluoronaphthalene) are fabricated,exhibiting two self-adaptive molecular stacking arrays.X-ray crystallographic analysis and theoretical calculation unveil their different π···π interactions and charge transfer characters,leading to the significant emission redshift up to 125 nm compared with individual DPPs.As a result,controllable molecule stacking structure,tunable emission,and charge transfer properties can be achieved.The study provides a new perspective to reveal the structure-property relationships at the molecular level by controlling the molecule configuration in cocrystal engineering,contributing to the development of cocrystal theoretical physics and organic functional materials.展开更多
Transition metal-catalyzed carbometallation of unsaturated hydrocarbons constitutes one of the most efficient synthetic methodologies for the construction of C—C bond.Recently,the incorporation of organometallic reag...Transition metal-catalyzed carbometallation of unsaturated hydrocarbons constitutes one of the most efficient synthetic methodologies for the construction of C—C bond.Recently,the incorporation of organometallic reagent with the CO gas as a nucleophilic acyl synthon could enable the acylmetallation reaction,which greatly increases the horizon of carbometallation chemistry.Herein,we report a nickel-catalyzed regiodivergent acylzincation of o-cyano cinnamate ester and o-cyano styrene,in which the cyano moiety intramolecularly captures zinc intermediates to trigger the tandem cyclization process.This protocol features mild conditions,broad substrate scope and excellent functional group tolerance,thus affording a diverse array of highly functionalized carbocyclic compounds.展开更多
The presence of protein aggregates in numerous human diseases underscores the significance of detecting these aggregates to comprehend disease mechanisms and develop novel therapeutic approaches for combating these di...The presence of protein aggregates in numerous human diseases underscores the significance of detecting these aggregates to comprehend disease mechanisms and develop novel therapeutic approaches for combating these disorders.Despite the development of various biosensors and fluorescent probes that selectively target amyloid fibers or amorphous aggregates,there is still a lack of tools capable of simultaneously detecting both types of aggregates.Herein,we demonstrate the quantitative discernment of amorphous aggregates by QM-FN-SO3,an aggregationinduced emission(AIE)probe initially designed for detecting amyloid fibers.This probe easily penetrates the membranes of the widely-used prokaryotic model organism Escherichia coli,enabling the visualization of both amorphous aggregates and amyloid fibers through near-infrared fluorescence.Notably,the probe exhibits sensitivity in distinguishing the varying aggregation propensities of proteins,regardless of whether they form amorphous aggregates or amyloid fibers in vivo.These properties contribute to the successful application of the QM-FN-SO3 probe in the subsequent investigation of the antiaggregation activities of two outer membrane protein(OMP)chaperones,both in vitro and in their physiological environment.Overall,our work introduces a near-infrared fluorescent chemical probe that can quantitatively detect amyloid fibers and amorphous aggregates with high sensitivity in vitro and in vivo.Furthermore,it demonstrates the applicability of the probe in chaperone biology and its potential as a high-throughput screening tool for protein aggregation inhibitors and folding factors.展开更多
Aging-related diseases are gradually becoming a major problem with the rapid development of aged population in human society.Although many fluorescent probes have been employed to diagnosis senescence via imaging sene...Aging-related diseases are gradually becoming a major problem with the rapid development of aged population in human society.Although many fluorescent probes have been employed to diagnosis senescence via imaging senescence-associatedβ-galactosidase(SA-β-Gal),which is proved to be closely associated with senescent cells,the similar catalytic effectiveness of enzymatic reaction of ovarian cancer-associatedβ-Gal(OA-β-Gal)will interfere with imaging accuracy.Herein,a near-infrared(NIR)hemicyanine based fluorescent probe HCyXA-βGal was designed for light-up imaging of live cells containingβ-Gal.With the organelle-targeting morpholinyl and positive charge moieties,HCyxA-βGal was successfully applicated to image the difference of enzymatic location in senescent cells and ovarian cancer cells.Furthermore,inspired by the fast response performance,fast and precise imaging of the two cell lines was realized via covering another dimension of fluorescence signal:time-dependent intensity.展开更多
Although considerable research efforts have been devoted to the design and development of non-noble electrocatalysts for oxygen evolution reaction(OER), substantial enhancement of OER performance with commercial-scale...Although considerable research efforts have been devoted to the design and development of non-noble electrocatalysts for oxygen evolution reaction(OER), substantial enhancement of OER performance with commercial-scale water electrolysis remains a big challenge. This could result from the difficulties in detecting the intrinsic properties and overlooking the assembly process for electrochemical OER process. Here, we employ a microjet collision method to investigate the intrinsic OER activities of individual NiZnFeO_x entities with and without a moderate magnetic field. Our results demonstrate that single NiZnFeO_x nanoparticles(NPs) show the excellent OER performance with a lowest onset potential(~1.35 V vs. RHE) and a greatest magnetic enhancement(~118%) among bulk materials, single agglomerations and NPs. Furthermore, we explore the utility of theoretical investigation by density functional theory(DFT)calculations for studying OER process on NiZnFeO_x surfaces without and with spin alignment, indicating monodispersed NiZnFeO_xNPs with totally spin alignment facilitates the OER process under the external magnetic field. It is found that the well-dispersion of NiZnFeO_x NPs would increase the electrical conductivity and the surface spin state, resulting in promoting their OER activities. This work provides a test for uncovering the essential roles of NPs assembly to a significant promotion of their magnet-assisted OER.展开更多
Controlling dynamic molecular self-assembly to finely tune macroscopic properties offers chemical solutions to rational material design.Here we report that combining disulfide-mediated ring-opening polymerization with...Controlling dynamic molecular self-assembly to finely tune macroscopic properties offers chemical solutions to rational material design.Here we report that combining disulfide-mediated ring-opening polymerization withβ-sheet-like H-bonding self-assembly can drive a direct small-molecular assembly into a layered ionic network with precise architectural tunability and controllable functions as ion-transport membranes.This strategy enables a one-step evaporationinduced self-assembly from discrete small molecules to layered ionic networks with high crystallinity.The interlayer distances can be readily engineered with nanometer accuracy by varying the length of the oligopeptide side chain.The synergy of the layered structure and hydrophilic terminal groups facilitates the formation and ordering of interlayer water channels,endowing the resulting membranes with high efficiency in transporting ions.Moreover,the inherent dynamic nature of poly(disulfide)s allows chemical recycling to monomers under mild conditions.We foresee that the robust strategy of combining dynamic disulfide chemistry and noncovalent assembly can afford many opportunities in designing smart materials with unique functions and applications.展开更多
There is a relatively low efficiency of Fe(Ⅲ)/Fe(Ⅱ) conversion cycle and H2 O2 decomposition(<30%) in conventional Fenton process,which further results in a low production efficiency of ·OH and seriously res...There is a relatively low efficiency of Fe(Ⅲ)/Fe(Ⅱ) conversion cycle and H2 O2 decomposition(<30%) in conventional Fenton process,which further results in a low production efficiency of ·OH and seriously restricts the application of Fenton.Herein,we report that the commercial MoO2 can be used as the cocatalyst in Fenton process to dramatically accelerate the oxidation of Lissamine rhodamine B(L-RhB),where the efficiency of Fe(Ⅲ)/Fe(Ⅱ) cycling is greatly enhanced in the Fenton reaction meanwhile.And the L-RhB solution could be degraded nearly 100% in 1 min in the MoO2 cocatalytic Fenton system under the optimal reaction condition,which is apparently better than that of the conventional Fenton system(~50%).Different from the conventional Fenton reaction where the ’OH plays an important role in the oxidation process,it shows that 1 O2 contributes most in the MoO2 cocatalytic Fenton reaction.However,it is found that the exposed Mo^4+ active sites on the surface of MoO2 powders can greatly promote the rate-limiting step of Fe^3+/Fe^2+ cycle conversion,thus minimizing the dosage of H2 O2(0.400 mmol/L) and Fe^2+(0.105 mmol/L).Interestingly,the MoO2 cocatalytic Fenton system also exhibits a good ability for reducing Cr(Ⅵ) ions,where the reduction ability for Cr(Ⅵ) reaches almost 100% within 2 h.In short,this work shows a new discovery for M002 cocatalytic advanced oxidation processes(AOPs),which devotes a lot to the practical water remediation application.展开更多
Water pollution is a global environmental issue with multi-dimensional infl uences on human life.Some strategies,such as photo-Fenton reaction,have been employed to remove recalcitrant pollutants.Two-dimensional(2D)gr...Water pollution is a global environmental issue with multi-dimensional infl uences on human life.Some strategies,such as photo-Fenton reaction,have been employed to remove recalcitrant pollutants.Two-dimensional(2D)graphene and its threedimensional(3D)confi gurations have attracted considerable attention as emerging carbon-based catalysts in photo-Fenton fi elds owing to their alluring properties in electron transfer,reactant adsorption,and light response.This review summarizes the recent developments in 2D and 3D graphene-based catalysts for photo-Fenton reactions.Their structures,characteristics,activity,and mechanisms are discussed.The conclusions and outlooks are proposed for the profound understanding of challenges and future directions.展开更多
Due to their simplicity in preparation,sensitivity and selectivity,fluorescent probes have become the analytical tool of choice in a wide range of research and industrial fields,facilitating the rapid detection of che...Due to their simplicity in preparation,sensitivity and selectivity,fluorescent probes have become the analytical tool of choice in a wide range of research and industrial fields,facilitating the rapid detection of chemical substances of interest as well as the study of important physiological and pathological processes at the cellular level.In addition,many long-wavelength fluorescent probes developed have also proven applicable for in vivo biomedical applications including fluorescenceguided disease diagnosis and theranostics(e.g.,fluorogenic prodrugs).Impressive progresses have been made in the development of sensing agents and materials for the detection of ions,organic small molecules,and biomacromolecules including enzymes,DNAs/RNAs,lipids,and carbohydrates that play crucial roles in biological and disease-relevant events.Here,we highlight examples of fluorescent probes and functional materials for biological applications selected from the special issues“Fluorescent Probes”and“Molecular Sensors and Logic Gates”recently published in this journal,offering insights into the future development of powerful fluorescence-based chemical tools for basic biological studies and clinical translation.展开更多
Suitable conformations and proper alignment of complex natural macrocycles are essential for achieving their unique properties.However,such artificial macrocycle prototypes are still limited due to synthetic difficult...Suitable conformations and proper alignment of complex natural macrocycles are essential for achieving their unique properties.However,such artificial macrocycle prototypes are still limited due to synthetic difficulties.In this respect,directly linked porphyrin analog dimers display tunable conformations and intriguing properties,and thus,they may be employed as a class of promising platforms.Herein,we report that one-pot oxidative dimerization of thiahydrosapphyrin 1 yields dimers,2anti and 2syn,comprising a transoid-oriented plate-like bipyrrolo[1,2-a]indolylidene.The thiophene-containing tetrapyrrole arching subunits in 2 lie at the opposite(anti)and same(syn)sides of the plate,respectively.Meanwhile,multiply fused cisoid-orientated dimer 3 was also obtained;a polycyclic pyrrolo-bridged bipyrroloindole derivative tethered with fullyπ-conjugated bridges was formed.Notably,the anti-dimer 2anti underwent subsequent oxidative fusion to furnish a further-fused[6.5.5.7.5.5.5.6]-octacyclic compound 4anti.In contrast,the syn-orientated 2syn could not be further fused due to the long distance between the potential reaction sites.This study provides a unique approach to the fused dimeric porphyrin analogs for potential near-infrared optical materials by a simple oxidation reaction.It also reveals the importance of conformation-modulated reactivity for constructing complex porphyrin arrays.展开更多
A bistable[2]rotaxane with a conformation-adaptive macrocycle bearing a 9,14-diphenyl-9,14-dihydrodibenzo[a,c]phenazine(DPAC)unit was synthesized,which could be utilized to optical probe the molecular shuttling motion...A bistable[2]rotaxane with a conformation-adaptive macrocycle bearing a 9,14-diphenyl-9,14-dihydrodibenzo[a,c]phenazine(DPAC)unit was synthesized,which could be utilized to optical probe the molecular shuttling motion of the functionalized rotaxane system.The UV-vis,^(1) H NMR and PL spectroscopic data clearly demonstrated that the DPAC ring was interlocked onto the thread and the fluorescence intensity of the DPAC unit in the macrocycle was effectively regulated by the location change of the macrocycle along the thread under acid/base stimulation,which was attributed to the modulation of the intramolecular photo-induced electron transfer between the DPAC unit and the methyltriazole(MTA)unit.This bistable rotaxane system containing a conformation-adaptive fluorophore unit in the macrocycle moiety opens an alternative way to design functional bistable mechanically interlocked molecules.展开更多
Electrical switching of a single-molecule junction provides a practical module to perform sophisticated operations in electronic devices.However,designing an all-electrically-driven molecular switch is a great challen...Electrical switching of a single-molecule junction provides a practical module to perform sophisticated operations in electronic devices.However,designing an all-electrically-driven molecular switch is a great challenge.Here,we experimentally and theoretically investigated the charge transport characteristics of isoindigo(ISO)-molecules at the single-molecule level using the scanning tunneling microscope break junction technique.We find that the single-molecule junctions of ISO-molecules display bias voltage-driven switching characteristics.These switches are realtime,reversible,and nondestructive under low-bias voltages.Experimental results show that the mechanism of the switch is not the transition from nonresonant charge transport to resonant charge transport,but it is the shift of the frontier orbital energy levels of ISO-molecules and the change of the interfacial electronic coupling with bias voltage.Our results will advance the design of high-performance bias voltage-driven molecular switches.展开更多
Deep-red/near-infrared fluorescence is highly suitable for bioimaging owing to its ability to deeply penetrate tissues,organs,and live animals.However,developing organic fluorophores with high deep-red/near-infrared f...Deep-red/near-infrared fluorescence is highly suitable for bioimaging owing to its ability to deeply penetrate tissues,organs,and live animals.However,developing organic fluorophores with high deep-red/near-infrared fluorescence quantum yield(Φ_(FL))and fluorescent brightness remain a significant challenge owing to the energy gap law.Herein,we developed a straightforward and effective chalcogen-annulation strategy by introducing O,S and Se into the bay region of TDI and QDI fluorophores,realizing the increase ofΦFLand fluorescent brightness up to 10 times.To our best knowledge,this study potentially stands as the pioneering instance showcasing the anti-heavy-atom effect of chalcogens,and the absoluteΦFL(93%)and fluorescent brightness(128,200 cm^(-1)mol^(-1)L)of Se-TDI is among top deep-red/near-infrared organic fluorophores currently available.The femtosecond transient absorption(fs-TA)measurements show the absence of obvious changes of the excited state lifetime after the introduction of chalcogens in TDI and QDI fluorophores,indicating that intersystem crossing(ISC)can be neglected in TDI and QDI fluorophores.Theoretical calculations further reveal the chalcogen-annulation strategy increase the radiative rates and reduce the reorganization energy of several accepting modes at the ground state in TDI fluorophores,leading to the suppression of internal conversion(IC)processes.Our chalcogen-annulation strategy,which effectively increases the Φ_(FL)and restricts the IC processes,while remaining unaffected by the heavy-atom effect,offers novel insights and theoretical support for the design and synthesis of deep-red/near-infrared organic fluorophores with high Φ_(FL)and fluorescent brightness.展开更多
Since the elucidation that sugar-lectin interactions contribute to the understanding of ‘‘Glycomics' ', how to construct glycosensors with rapid response, excellent sensitivity and selectivity is of intense ...Since the elucidation that sugar-lectin interactions contribute to the understanding of ‘‘Glycomics' ', how to construct glycosensors with rapid response, excellent sensitivity and selectivity is of intense research interest. Herein, we report the design of three NIR emissive glyco-probes based on diketopyrrolopyrrole(DPPs) conjugated with two(DPPG), four(DPPF-G) and six(DPPS-G) galactose groups. All three molecules could probe lectins with excellent sensitivity and selectivity. The increase of glyco-DPP emission in NIR region upon interaction with lectin is due to the aggregates formation induced by sugar-lectin interactions, which have been verified by dynamic light scattering(DLS) and scanning electronic microscope(SEM) analysis.Due to the multiple glyco-ligands on DPPS-G, it has been successfully used to stain Hep G2 cells through interactions between galactose and asialogly-coprotein(ASGP-R), which are overexpressed on the surface of Hep G2 cells.展开更多
The addition and substitution reactions across a variety of alkenes and alkynes have been playing an important role in organic synthesis.In particular,catalyses enabled by homogeneous complexes as well as heterogenous...The addition and substitution reactions across a variety of alkenes and alkynes have been playing an important role in organic synthesis.In particular,catalyses enabled by homogeneous complexes as well as heterogenous nanomaterials have been much received attentions over decades.Along with these blooming progresses in these fields,single-atom site catalysts(SACs)exhibit outstanding performances in terms of reactivity and selectivity,thus providing a new powerful strategy to upgrade these bulk chemicals.Herein,we summarize the reactions of alkenes and alkynes enabled by SACs,in which catalytic hydrogenation,hydrosilylation,hydroboration,hydroformylation,and cross coupling have been included.Moreover,preparations and fine structures of the corresponding SACs have been described,therefore providing a better understanding and overview to address the origin of catalytic activity in the reported examples.展开更多
Charge-transporting layers(CTLs)are important in determining the performance and stability of perovskite solar cells(PSCs).Recently,there has been considerable use of self-assembled monolayers(SAMs)as charge-selective...Charge-transporting layers(CTLs)are important in determining the performance and stability of perovskite solar cells(PSCs).Recently,there has been considerable use of self-assembled monolayers(SAMs)as charge-selective contacts,especially for hole-selective SAMs in inverted PSCs as well as perovskite involving tandem solar cells.The SAM-based charge-selective contact shows many advantages over traditional thin-film organic/inorganic CTLs,including reduced cost,low optical and electric loss,conformal coating on a rough substrate,simple deposition on a large-area substrate and easy modulation of energy levels,molecular dipoles and surface properties.The incorporation of various hole-selective SAMs has resulted in high-efficiency single junction and tandem solar cells.This topical review summarizes both the advantages and challenges of SAM-based charge-selective contacts,and discusses the potential direction for future studies.展开更多
Molecularly near-infrared(NIR) theranostics, combining in vivo sensing and tumor-specific therapeutic capability within one molecular system, have received considerable attention in recent years. Compared with the vis...Molecularly near-infrared(NIR) theranostics, combining in vivo sensing and tumor-specific therapeutic capability within one molecular system, have received considerable attention in recent years. Compared with the visible fluorescence imaging, NIR imaging(emission wavelength at 650–900 nm) possesses unique advantages including the minimum photodamage to biological samples, deep penetration, and low interference from auto-fluorescence. In over past decades, there has been an explosive development in the design of molecular imaging contrasts and imaging-guided therapeutics. In this review, we have sumarried the strategies of the NIR theranostics for imaging and tumor-specific chemotherapy applications in living systems. It is noted that the molecularly NIR theranostic design strategy could address current challenges of real-time in vivo sense-and-release for the intelligent biosensing and personalized treatment.展开更多
In recent years, MoS_(2) catalyzed/cocatalyzed Fenton/Fenton-like systems have attracted wide attention in the field of pollution control, but there are few studies on the effect of H_(2)O_(2) feeding way on the whole...In recent years, MoS_(2) catalyzed/cocatalyzed Fenton/Fenton-like systems have attracted wide attention in the field of pollution control, but there are few studies on the effect of H_(2)O_(2) feeding way on the whole Fenton process. Here, we report a new type of composite catalyst (MoS_(2)-Fe_(x)) prepared in a simple way with highly dispersed iron to provide more active sites. MoS_(2)-Fe_(x) was proved to possess selectivity for singlet oxygen (^(1)O_(2)) in effectively degrading sulfadiazine with a wide pH adaptability (4.0~10.0). Importantly, the mechanism of the interaction between H_(2)O_(2) and MoS_(2) on the Fenton reaction activity was revealed through the combination of experiment and density functional theory (DFT) calculations. Compared to the traditional “a large amount for one time” feeding way of H_(2)O_(2), the “small amount for multiple times” of H_(2)O_(2) feeding way can increase the degradation rate of sulfadiazine from 36.9% to 91.1% in the MoS_(2)-Fe_(x) heterogeneous Fenton system. It is demonstrated that the “small amount for multiple times” of H_(2)O_(2) feeding way can reduce the side reaction of decomposition of H_(2)O_(2) by MoS_(2) and effectively improve the utilization rate of H_(2)O_(2) and the stability of MoS_(2)-Fe_(x). Compared with Fe_(2)O_(3)^(-)based Fenton system, MoS_(2)-Fe_(x) can significantly save the amount of H_(2)O_(2). Compared with nano-iron powder, the formation of iron sludge in MoS_(2)-Fe_(x) system was significantly reduced. Furthermore, long-term degradation test showed that the MoS_(2)-Fe75/H_(2)O_(2) system could maintain the effectiveness of degrading organic pollutants for 10 days (or even longer). This study has a guiding significance for the large-scale treatment of industrial wastewater by improved Fenton technology in the future.展开更多
基金supported financially by the National Natural Science Foundation of China(Nos.21832002,21808063,22002043,21872050)。
文摘The depolymerization and upgrading of lignin from raw biomass,while keeping cellulose intact is important in biorefinery and various metal-based catalysts have been used in reductive catalytic fractionation,a key method in"lignin-first"strategy,Recently,we found that a core-shell structured Co@CoO catalyst with CoO shell as the real active site had excellent performance in the hydrogenolysis of 5-hydromethylfurfural to 2,5-dimethylfuran due to its unique ability to dissociate H_(2)and yield active H^(δ-)species(Xiang et al.,2022).In this work,we report a one-pot depolymerization and upgrading of lignocellulose to alkylcyclohexanols,a flavour precursor,with intact cellulose over this unique core-shell structured catalyst,Co@CoO.Lignin model compounds(β-O-4,4-O-5,α-O-4)were first used to clarify the activity of Co@CoO catalyst.Then,the one-pot conversion of various organosolv lignin(birch,pine and poplar)to alkylcyclohexanols was realized with the mass yield of alkylcyclohexanols up to25.8 wt%from birch lignin under the reaction condition of 210℃,1 MPa H_(2),16 h.Finally,the corresponding woody sawdusts were used as feedstocks and found that the Co@CoO catalyst indeed preferentially depolymerized and upgraded the lignin part and obtained the same alkylcyclohexanols products with the retention of cellulose-rich pulp.The collected alkylcyclohexanols were further esterified to obtain valueadded esters,which can be used as flavors.This work will inspire the design of new efficient metal oxide catalysts in lignin fractionation and depolymerization to high-value-added chemicals with intact cellulose.
基金the National Natural Science Foundation of China(No.21832002)the Fund of the Science and Technology Commission of Shanghai Municipality,China(STCSM,No.10dz2220500).
文摘The interface between Au and support has attracted extensive interest because of its unique catalytic ability for hydrogen activation in catalytic hydrogenation/hydrogenolysis reactions.Herein,we create the Au-CoO-OV interface in the 1.0%Au/Co3O4-Rod-250 catalyst,which could dissociate H2 via the heterolytic way to yield rich hydride species and achieve excellent catalytic performance in the hydrogenolysis of biomass-derived 5-hydroxymethylfurfural(HMF)to 2,5-dimethylfuran(DMF).The XRD and HRTEM analyses show that Au nanoparticles are uniformly dispersed on CoO-OV surface and in situ DRIFTS spectra show the enhancement of heterolytic dissociation of hydrogen(signals of Au-D and O-D vibration)compared with bare CoO(Co3O4-Rod-250).This work provides insights for fabricating highly active Au-support catalysts for catalytic hydrogenation/hydrogenolysis reactions.
基金supported by the National Natural Science Foundation of China (22335004,22004036,22175063)the Shanghai Municipal Science&Technology Major Project (2018SHZDZX-03)+2 种基金the 111 Project (B16017)Shanghai Committee of Science&Technology (17520750100)the Program for Eastern Scholar Distinguished Professor。
文摘Organic cocrystal as an emerging assembly strategy has received increasing attention in constructing multiple functional materials,through continually screening suitable constituent monomers or changing their stoichiometry ratios.However,the role of molecule configuration in the cocrystal field is rarely explored despite the fascinating potential in regulating the packing mode.In this study,the N,N′-diphenyl-5,10-dihydrophenazine derivatives(DPPs) with the flexible scaffold and different methyl substitutions are selected as the donors bearing various molecular configurations.In a simple collaborative way,a series of cocrystals based on DPPs and OFN(octafluoronaphthalene) are fabricated,exhibiting two self-adaptive molecular stacking arrays.X-ray crystallographic analysis and theoretical calculation unveil their different π···π interactions and charge transfer characters,leading to the significant emission redshift up to 125 nm compared with individual DPPs.As a result,controllable molecule stacking structure,tunable emission,and charge transfer properties can be achieved.The study provides a new perspective to reveal the structure-property relationships at the molecular level by controlling the molecule configuration in cocrystal engineering,contributing to the development of cocrystal theoretical physics and organic functional materials.
基金supported by the National Natural Science Foundation of China(22171079,22371071)the Natural Science Foundation of Shanghai(21ZR1480400)+5 种基金the Shanghai Rising-Star Program(20QA1402300)the Shanghai Sailing Program(23YF1408800)the Shanghai Municipal Science and Technology Major Project(Grant No.2018SHZDZX03)the Program of Introducing Talents of Discipline to Universities(B16017)the China Postdoctoral Science Foundation(2021M701197,2023T160215)the Fundamental Research Funds for the Central Universities.
文摘Transition metal-catalyzed carbometallation of unsaturated hydrocarbons constitutes one of the most efficient synthetic methodologies for the construction of C—C bond.Recently,the incorporation of organometallic reagent with the CO gas as a nucleophilic acyl synthon could enable the acylmetallation reaction,which greatly increases the horizon of carbometallation chemistry.Herein,we report a nickel-catalyzed regiodivergent acylzincation of o-cyano cinnamate ester and o-cyano styrene,in which the cyano moiety intramolecularly captures zinc intermediates to trigger the tandem cyclization process.This protocol features mild conditions,broad substrate scope and excellent functional group tolerance,thus affording a diverse array of highly functionalized carbocyclic compounds.
基金Natural Science Foundation of Shanghai,Grant/Award Number:23ZR1415300National Natural Science Foundation of China,Grant/Award Numbers:32222049,31661143021,32171269,32201043+1 种基金National Key Research and Development Program of China,Grant/Award Number:2022YFF1102900Shanghai Frontier Science Center of Optogenetic Techniques for Cell Metabolism Shanghai Municipal Education Commission,Grant/Award Number:2021Sci&Tech0328。
文摘The presence of protein aggregates in numerous human diseases underscores the significance of detecting these aggregates to comprehend disease mechanisms and develop novel therapeutic approaches for combating these disorders.Despite the development of various biosensors and fluorescent probes that selectively target amyloid fibers or amorphous aggregates,there is still a lack of tools capable of simultaneously detecting both types of aggregates.Herein,we demonstrate the quantitative discernment of amorphous aggregates by QM-FN-SO3,an aggregationinduced emission(AIE)probe initially designed for detecting amyloid fibers.This probe easily penetrates the membranes of the widely-used prokaryotic model organism Escherichia coli,enabling the visualization of both amorphous aggregates and amyloid fibers through near-infrared fluorescence.Notably,the probe exhibits sensitivity in distinguishing the varying aggregation propensities of proteins,regardless of whether they form amorphous aggregates or amyloid fibers in vivo.These properties contribute to the successful application of the QM-FN-SO3 probe in the subsequent investigation of the antiaggregation activities of two outer membrane protein(OMP)chaperones,both in vitro and in their physiological environment.Overall,our work introduces a near-infrared fluorescent chemical probe that can quantitatively detect amyloid fibers and amorphous aggregates with high sensitivity in vitro and in vivo.Furthermore,it demonstrates the applicability of the probe in chaperone biology and its potential as a high-throughput screening tool for protein aggregation inhibitors and folding factors.
基金supported by National Natural Science Foundation of China(Nos.22122803 and 21788102)the National Natural Science Foundation of Jiangsu Province(No.BK20220644).
文摘Aging-related diseases are gradually becoming a major problem with the rapid development of aged population in human society.Although many fluorescent probes have been employed to diagnosis senescence via imaging senescence-associatedβ-galactosidase(SA-β-Gal),which is proved to be closely associated with senescent cells,the similar catalytic effectiveness of enzymatic reaction of ovarian cancer-associatedβ-Gal(OA-β-Gal)will interfere with imaging accuracy.Herein,a near-infrared(NIR)hemicyanine based fluorescent probe HCyXA-βGal was designed for light-up imaging of live cells containingβ-Gal.With the organelle-targeting morpholinyl and positive charge moieties,HCyxA-βGal was successfully applicated to image the difference of enzymatic location in senescent cells and ovarian cancer cells.Furthermore,inspired by the fast response performance,fast and precise imaging of the two cell lines was realized via covering another dimension of fluorescence signal:time-dependent intensity.
基金supported by the Major Research Project (No.92061108)the National Natural Science Foundation of China (No.22272052)+2 种基金Shanghai Municipal Science and Technology Major Project (No. 2018SHZDZX03)Xiamen University Opening Project of PCOSS (No. 201901)Yongjiang Talent Introduction Programme(No. 2021A-115-G)。
文摘Although considerable research efforts have been devoted to the design and development of non-noble electrocatalysts for oxygen evolution reaction(OER), substantial enhancement of OER performance with commercial-scale water electrolysis remains a big challenge. This could result from the difficulties in detecting the intrinsic properties and overlooking the assembly process for electrochemical OER process. Here, we employ a microjet collision method to investigate the intrinsic OER activities of individual NiZnFeO_x entities with and without a moderate magnetic field. Our results demonstrate that single NiZnFeO_x nanoparticles(NPs) show the excellent OER performance with a lowest onset potential(~1.35 V vs. RHE) and a greatest magnetic enhancement(~118%) among bulk materials, single agglomerations and NPs. Furthermore, we explore the utility of theoretical investigation by density functional theory(DFT)calculations for studying OER process on NiZnFeO_x surfaces without and with spin alignment, indicating monodispersed NiZnFeO_xNPs with totally spin alignment facilitates the OER process under the external magnetic field. It is found that the well-dispersion of NiZnFeO_x NPs would increase the electrical conductivity and the surface spin state, resulting in promoting their OER activities. This work provides a test for uncovering the essential roles of NPs assembly to a significant promotion of their magnet-assisted OER.
基金This work was supported by the National Natural Science Foundation of China(grant nos.22025503,21790361,21788102,and 21871084)Shanghai Municipal Science and Technology Major Project(grant no.2018SHZDZX03)+2 种基金the Fundamental Research Funds for the Central Universities,the Programme of Introducing Talents of Discipline to Universities(grant no.B16017)Program of Shanghai Academic/Technology Research Leader(grant no.19XD1421100),Science and Technology Commission of Shanghai Municipality(grant no.21JC1401700)the Starry Night Science Fund of Zhejiang University Shanghai Institute for Advanced Study(grant no.SN-ZJU-SIAS-006).The authors thank the Research Center of Analysis and Test of East China University of Science and Technology for help on the material characterization.
文摘Controlling dynamic molecular self-assembly to finely tune macroscopic properties offers chemical solutions to rational material design.Here we report that combining disulfide-mediated ring-opening polymerization withβ-sheet-like H-bonding self-assembly can drive a direct small-molecular assembly into a layered ionic network with precise architectural tunability and controllable functions as ion-transport membranes.This strategy enables a one-step evaporationinduced self-assembly from discrete small molecules to layered ionic networks with high crystallinity.The interlayer distances can be readily engineered with nanometer accuracy by varying the length of the oligopeptide side chain.The synergy of the layered structure and hydrophilic terminal groups facilitates the formation and ordering of interlayer water channels,endowing the resulting membranes with high efficiency in transporting ions.Moreover,the inherent dynamic nature of poly(disulfide)s allows chemical recycling to monomers under mild conditions.We foresee that the robust strategy of combining dynamic disulfide chemistry and noncovalent assembly can afford many opportunities in designing smart materials with unique functions and applications.
基金supported by the State Key Research Development Program of China (No.2016YFA0204200)National Natural Science Foundation of China (Nos.21822603,21811540394,5171101651,21677048,21773062,21577036)+3 种基金Shanghai Pujiang Program (No.17PJD011)the Fundamental Research Funds for the Central Universities (No.22A201514021)Project supported by Shanghai Municipal Science and Technology Major Project (No. 2018SHZDZX03)the Program of Introducing Talents of Discipline to Universities (No.B16017)
文摘There is a relatively low efficiency of Fe(Ⅲ)/Fe(Ⅱ) conversion cycle and H2 O2 decomposition(<30%) in conventional Fenton process,which further results in a low production efficiency of ·OH and seriously restricts the application of Fenton.Herein,we report that the commercial MoO2 can be used as the cocatalyst in Fenton process to dramatically accelerate the oxidation of Lissamine rhodamine B(L-RhB),where the efficiency of Fe(Ⅲ)/Fe(Ⅱ) cycling is greatly enhanced in the Fenton reaction meanwhile.And the L-RhB solution could be degraded nearly 100% in 1 min in the MoO2 cocatalytic Fenton system under the optimal reaction condition,which is apparently better than that of the conventional Fenton system(~50%).Different from the conventional Fenton reaction where the ’OH plays an important role in the oxidation process,it shows that 1 O2 contributes most in the MoO2 cocatalytic Fenton reaction.However,it is found that the exposed Mo^4+ active sites on the surface of MoO2 powders can greatly promote the rate-limiting step of Fe^3+/Fe^2+ cycle conversion,thus minimizing the dosage of H2 O2(0.400 mmol/L) and Fe^2+(0.105 mmol/L).Interestingly,the MoO2 cocatalytic Fenton system also exhibits a good ability for reducing Cr(Ⅵ) ions,where the reduction ability for Cr(Ⅵ) reaches almost 100% within 2 h.In short,this work shows a new discovery for M002 cocatalytic advanced oxidation processes(AOPs),which devotes a lot to the practical water remediation application.
文摘Water pollution is a global environmental issue with multi-dimensional infl uences on human life.Some strategies,such as photo-Fenton reaction,have been employed to remove recalcitrant pollutants.Two-dimensional(2D)graphene and its threedimensional(3D)confi gurations have attracted considerable attention as emerging carbon-based catalysts in photo-Fenton fi elds owing to their alluring properties in electron transfer,reactant adsorption,and light response.This review summarizes the recent developments in 2D and 3D graphene-based catalysts for photo-Fenton reactions.Their structures,characteristics,activity,and mechanisms are discussed.The conclusions and outlooks are proposed for the profound understanding of challenges and future directions.
基金the National Natural Science Foundation of China(Grant Nos.21907030 and 22108077)the International Cooperation Program of Shanghai Science and Technology Committee(Grant No.19410712600)+4 种基金De-Tai Shi would like to thank the Natural Science Foundation of Jiangxi(Grant No.20161BAB213067)the Scientific Research Fund of Jiangxi Provincial Education Department(Grant No.GJJ170807)Tony D.James wishes to thank the Royal Society for a Wolfson Research Merit Awardthe Open Research Fund of the School of ChemistryChemical Engineering,Henan Normal University for support(Grant No.2020ZD01).
文摘Due to their simplicity in preparation,sensitivity and selectivity,fluorescent probes have become the analytical tool of choice in a wide range of research and industrial fields,facilitating the rapid detection of chemical substances of interest as well as the study of important physiological and pathological processes at the cellular level.In addition,many long-wavelength fluorescent probes developed have also proven applicable for in vivo biomedical applications including fluorescenceguided disease diagnosis and theranostics(e.g.,fluorogenic prodrugs).Impressive progresses have been made in the development of sensing agents and materials for the detection of ions,organic small molecules,and biomacromolecules including enzymes,DNAs/RNAs,lipids,and carbohydrates that play crucial roles in biological and disease-relevant events.Here,we highlight examples of fluorescent probes and functional materials for biological applications selected from the special issues“Fluorescent Probes”and“Molecular Sensors and Logic Gates”recently published in this journal,offering insights into the future development of powerful fluorescence-based chemical tools for basic biological studies and clinical translation.
基金The authors thank the Research Center of Analysis and Test of East China University of Science and Technology for compound characterization.
文摘Suitable conformations and proper alignment of complex natural macrocycles are essential for achieving their unique properties.However,such artificial macrocycle prototypes are still limited due to synthetic difficulties.In this respect,directly linked porphyrin analog dimers display tunable conformations and intriguing properties,and thus,they may be employed as a class of promising platforms.Herein,we report that one-pot oxidative dimerization of thiahydrosapphyrin 1 yields dimers,2anti and 2syn,comprising a transoid-oriented plate-like bipyrrolo[1,2-a]indolylidene.The thiophene-containing tetrapyrrole arching subunits in 2 lie at the opposite(anti)and same(syn)sides of the plate,respectively.Meanwhile,multiply fused cisoid-orientated dimer 3 was also obtained;a polycyclic pyrrolo-bridged bipyrroloindole derivative tethered with fullyπ-conjugated bridges was formed.Notably,the anti-dimer 2anti underwent subsequent oxidative fusion to furnish a further-fused[6.5.5.7.5.5.5.6]-octacyclic compound 4anti.In contrast,the syn-orientated 2syn could not be further fused due to the long distance between the potential reaction sites.This study provides a unique approach to the fused dimeric porphyrin analogs for potential near-infrared optical materials by a simple oxidation reaction.It also reveals the importance of conformation-modulated reactivity for constructing complex porphyrin arrays.
基金supported by the National Natural Science Foundation of China(Nos.22025503,21790361 and 21871084)Shanghai Municipal Science and Technology Major Project(No.2018SHZDZX03)+3 种基金the Fundamental Research Funds for the Central Universitiesthe Program of Introducing Talents of Discipline to Universities(No.B16017)the Shanghai Science and Technology Committee(No.17520750100)funding from China Postdoctoral Science Foundation funded project(No.J100–5R-20130)。
文摘A bistable[2]rotaxane with a conformation-adaptive macrocycle bearing a 9,14-diphenyl-9,14-dihydrodibenzo[a,c]phenazine(DPAC)unit was synthesized,which could be utilized to optical probe the molecular shuttling motion of the functionalized rotaxane system.The UV-vis,^(1) H NMR and PL spectroscopic data clearly demonstrated that the DPAC ring was interlocked onto the thread and the fluorescence intensity of the DPAC unit in the macrocycle was effectively regulated by the location change of the macrocycle along the thread under acid/base stimulation,which was attributed to the modulation of the intramolecular photo-induced electron transfer between the DPAC unit and the methyltriazole(MTA)unit.This bistable rotaxane system containing a conformation-adaptive fluorophore unit in the macrocycle moiety opens an alternative way to design functional bistable mechanically interlocked molecules.
基金supported by the National Natural Science Foundation of China(grant nos.21875279,22075080,and 52273176)the Shanghai Municipal Science and Technology Major Project(grant no.2018SHZDZX03)the Fundamental Research Funds for the Central Universities,and East China University of Science and Technology.
文摘Electrical switching of a single-molecule junction provides a practical module to perform sophisticated operations in electronic devices.However,designing an all-electrically-driven molecular switch is a great challenge.Here,we experimentally and theoretically investigated the charge transport characteristics of isoindigo(ISO)-molecules at the single-molecule level using the scanning tunneling microscope break junction technique.We find that the single-molecule junctions of ISO-molecules display bias voltage-driven switching characteristics.These switches are realtime,reversible,and nondestructive under low-bias voltages.Experimental results show that the mechanism of the switch is not the transition from nonresonant charge transport to resonant charge transport,but it is the shift of the frontier orbital energy levels of ISO-molecules and the change of the interfacial electronic coupling with bias voltage.Our results will advance the design of high-performance bias voltage-driven molecular switches.
基金financially supported by the National Natural Science Foundation of China(NSFC)(22235005)the National Postdoctoral Program for Innovative Talents(BX20200128)+3 种基金the 69th batch of Chinese postdoctoral general support(2021M691004)Shanghai Municipal Science and Technology Major Project(2018SHZDZX03)the Fundamental Research Funds for the Central Universitiesthe Programme of Introducing Talents of Discipline to Universities(B16017)。
文摘Deep-red/near-infrared fluorescence is highly suitable for bioimaging owing to its ability to deeply penetrate tissues,organs,and live animals.However,developing organic fluorophores with high deep-red/near-infrared fluorescence quantum yield(Φ_(FL))and fluorescent brightness remain a significant challenge owing to the energy gap law.Herein,we developed a straightforward and effective chalcogen-annulation strategy by introducing O,S and Se into the bay region of TDI and QDI fluorophores,realizing the increase ofΦFLand fluorescent brightness up to 10 times.To our best knowledge,this study potentially stands as the pioneering instance showcasing the anti-heavy-atom effect of chalcogens,and the absoluteΦFL(93%)and fluorescent brightness(128,200 cm^(-1)mol^(-1)L)of Se-TDI is among top deep-red/near-infrared organic fluorophores currently available.The femtosecond transient absorption(fs-TA)measurements show the absence of obvious changes of the excited state lifetime after the introduction of chalcogens in TDI and QDI fluorophores,indicating that intersystem crossing(ISC)can be neglected in TDI and QDI fluorophores.Theoretical calculations further reveal the chalcogen-annulation strategy increase the radiative rates and reduce the reorganization energy of several accepting modes at the ground state in TDI fluorophores,leading to the suppression of internal conversion(IC)processes.Our chalcogen-annulation strategy,which effectively increases the Φ_(FL)and restricts the IC processes,while remaining unaffected by the heavy-atom effect,offers novel insights and theoretical support for the design and synthesis of deep-red/near-infrared organic fluorophores with high Φ_(FL)and fluorescent brightness.
基金supported by the National Natural Science Foundation of China (21772040, 21421004, 21372082, 21572062)the Fundamental Research Funds for the Central Universities (222201717003)+4 种基金the Programme of Introducing Talents of Discipline to Universities (B16017)a Visiting Program at NUS of China Scholarship Council (CSC)the Singapore Ministry of Education (R279-000-391-112)Singapore NRF Investigatorship (R279-000-444-281)the National University of Singapore (R279-000-482-133)
文摘Since the elucidation that sugar-lectin interactions contribute to the understanding of ‘‘Glycomics' ', how to construct glycosensors with rapid response, excellent sensitivity and selectivity is of intense research interest. Herein, we report the design of three NIR emissive glyco-probes based on diketopyrrolopyrrole(DPPs) conjugated with two(DPPG), four(DPPF-G) and six(DPPS-G) galactose groups. All three molecules could probe lectins with excellent sensitivity and selectivity. The increase of glyco-DPP emission in NIR region upon interaction with lectin is due to the aggregates formation induced by sugar-lectin interactions, which have been verified by dynamic light scattering(DLS) and scanning electronic microscope(SEM) analysis.Due to the multiple glyco-ligands on DPPS-G, it has been successfully used to stain Hep G2 cells through interactions between galactose and asialogly-coprotein(ASGP-R), which are overexpressed on the surface of Hep G2 cells.
基金J.Z.acknowledges Project supported by Shanghai Municipal Science and Technology Major Project(No.2018SHZDZX03)the Program of Introducing Talents of Discipline to Universities(No.B16017).
文摘The addition and substitution reactions across a variety of alkenes and alkynes have been playing an important role in organic synthesis.In particular,catalyses enabled by homogeneous complexes as well as heterogenous nanomaterials have been much received attentions over decades.Along with these blooming progresses in these fields,single-atom site catalysts(SACs)exhibit outstanding performances in terms of reactivity and selectivity,thus providing a new powerful strategy to upgrade these bulk chemicals.Herein,we summarize the reactions of alkenes and alkynes enabled by SACs,in which catalytic hydrogenation,hydrosilylation,hydroboration,hydroformylation,and cross coupling have been included.Moreover,preparations and fine structures of the corresponding SACs have been described,therefore providing a better understanding and overview to address the origin of catalytic activity in the reported examples.
基金supported by the National Natural Science Foundation of China(Grant No.22179037)the Fundamental Research Funds for the Central Universities.Thanks for the financial support of‘Zhang Jiangshu’cultivation program.The authors declare no competing interests.
文摘Charge-transporting layers(CTLs)are important in determining the performance and stability of perovskite solar cells(PSCs).Recently,there has been considerable use of self-assembled monolayers(SAMs)as charge-selective contacts,especially for hole-selective SAMs in inverted PSCs as well as perovskite involving tandem solar cells.The SAM-based charge-selective contact shows many advantages over traditional thin-film organic/inorganic CTLs,including reduced cost,low optical and electric loss,conformal coating on a rough substrate,simple deposition on a large-area substrate and easy modulation of energy levels,molecular dipoles and surface properties.The incorporation of various hole-selective SAMs has resulted in high-efficiency single junction and tandem solar cells.This topical review summarizes both the advantages and challenges of SAM-based charge-selective contacts,and discusses the potential direction for future studies.
基金supported by the National Natural Science Foundation of China (Nos.2 788102, 21421004, 21636002, 21622602 and 21908060)National Key Research and Development Program (No. 2017YFC0906902)+2 种基金Shanghai Municipal Science and Technology Major Project (No. 2018SHZDZX03)the Innovation Program of Shanghai Municipal Education Commission, Scientific Committee of Shanghai (No. 15XD1501400)China Postdoctoral Science Foundation (No. 2019M651417)
文摘Molecularly near-infrared(NIR) theranostics, combining in vivo sensing and tumor-specific therapeutic capability within one molecular system, have received considerable attention in recent years. Compared with the visible fluorescence imaging, NIR imaging(emission wavelength at 650–900 nm) possesses unique advantages including the minimum photodamage to biological samples, deep penetration, and low interference from auto-fluorescence. In over past decades, there has been an explosive development in the design of molecular imaging contrasts and imaging-guided therapeutics. In this review, we have sumarried the strategies of the NIR theranostics for imaging and tumor-specific chemotherapy applications in living systems. It is noted that the molecularly NIR theranostic design strategy could address current challenges of real-time in vivo sense-and-release for the intelligent biosensing and personalized treatment.
基金supported by the State Key Research Development Program of China (No. 2016YFA0204200)Project supported by Shanghai Municipal Science and Technology Major Project (No.2018SHZDZX03)+2 种基金the Program of Introducing Talents of Discipline to Universities (No. B16017)National Natural Science Foundation of China (No. 21822603)the Science and Technology Commission of Shanghai Municipality (No. 20DZ2250400)。
文摘In recent years, MoS_(2) catalyzed/cocatalyzed Fenton/Fenton-like systems have attracted wide attention in the field of pollution control, but there are few studies on the effect of H_(2)O_(2) feeding way on the whole Fenton process. Here, we report a new type of composite catalyst (MoS_(2)-Fe_(x)) prepared in a simple way with highly dispersed iron to provide more active sites. MoS_(2)-Fe_(x) was proved to possess selectivity for singlet oxygen (^(1)O_(2)) in effectively degrading sulfadiazine with a wide pH adaptability (4.0~10.0). Importantly, the mechanism of the interaction between H_(2)O_(2) and MoS_(2) on the Fenton reaction activity was revealed through the combination of experiment and density functional theory (DFT) calculations. Compared to the traditional “a large amount for one time” feeding way of H_(2)O_(2), the “small amount for multiple times” of H_(2)O_(2) feeding way can increase the degradation rate of sulfadiazine from 36.9% to 91.1% in the MoS_(2)-Fe_(x) heterogeneous Fenton system. It is demonstrated that the “small amount for multiple times” of H_(2)O_(2) feeding way can reduce the side reaction of decomposition of H_(2)O_(2) by MoS_(2) and effectively improve the utilization rate of H_(2)O_(2) and the stability of MoS_(2)-Fe_(x). Compared with Fe_(2)O_(3)^(-)based Fenton system, MoS_(2)-Fe_(x) can significantly save the amount of H_(2)O_(2). Compared with nano-iron powder, the formation of iron sludge in MoS_(2)-Fe_(x) system was significantly reduced. Furthermore, long-term degradation test showed that the MoS_(2)-Fe75/H_(2)O_(2) system could maintain the effectiveness of degrading organic pollutants for 10 days (or even longer). This study has a guiding significance for the large-scale treatment of industrial wastewater by improved Fenton technology in the future.
