The development of high-performance transition metal sulfide(TMS)/carbon composites to replace conventional graphite anode remains a critical challenge for advancing lithium-ion batteries(LIBs).In this study,a facile ...The development of high-performance transition metal sulfide(TMS)/carbon composites to replace conventional graphite anode remains a critical challenge for advancing lithium-ion batteries(LIBs).In this study,a facile self-sacrifice template method is developed to prepare FeS encapsulated into N,S co-doped carbon(FeS/NSC)composite using melamine-cyanuric acid(MCA)supermolecule as a multifunctional template precursor.The function of MCA supermolecule for material synthesis is explored,revealing its special function as a dispersant,dopant and pore-forming agent.Furthermore,the effect of Fe source dosage on the morphology,structure and composition of the final products is explored.The resultant FeS/NSC-0.1(where 0.1 represents the mass of added Fe source)exhibits the most optimal proportion,characterized by a good dispersion status of FeS within the NSC matrix,effective N,S co-doping and ample porosity.Benefiting from these merits,the FeS/NSC-0.1 anode demonstrates significantly improved cycling stability and rate capability when compared to the counterparts.Undoubtedly,this work offers a universal method to produce advanced transition metal sulfide/carbon composite electrodes for energy storage and conversion systems.展开更多
Electrocatalytic N_(2)reduction reaction (NRR) has been considered as a promising and alternative strategy for the synthesis of NH_(3),which will contribute to the goal of carbon neutrality and sustainability.However,...Electrocatalytic N_(2)reduction reaction (NRR) has been considered as a promising and alternative strategy for the synthesis of NH_(3),which will contribute to the goal of carbon neutrality and sustainability.However,this process often suffers from the barrier for N_(2)activation and competitive reactions,resulting in poor NH_(3)yield and low Faraday efficiency (FE).Here,we report a two-dimensiona(2D) ultrathin FeS nanosheets with high conductivity through a facile and scalable method under mild condition.The synthesized FeS catalysts can be used as the work electrode in the electrochemical NRR cell with N_(2)-saturated Na_(2)SO_(4)electrolyte.Such a catalyst shows a NH_(3)yield of 9.0μg·h^(-1)·mg^(-1)(corresponding to 1.47×10^(-4)μmol·s^(-1)·cm^(-2)) and a high FE of 12.4%,which significantly outperformed the other most NRR catalysts.The high catalytic performance of FeS can be attributed to the 2D mackinawite structure,which provides a new insight to explore low-cost and high-performance Fe-based electrocatalysts,as well as accelerates the practical application of the NRR.展开更多
The degradation of organic pollutants in water is a critical environmental challenge.The iron-doped MoS_(2) catalysts have demonstrated potential in activating peroxymonosulfate(PMS)for environmental remediation,but t...The degradation of organic pollutants in water is a critical environmental challenge.The iron-doped MoS_(2) catalysts have demonstrated potential in activating peroxymonosulfate(PMS)for environmental remediation,but they face challenges such as poor conductivity,limited electron transfer efficiency,and a scarcity of active sites.To address these issues,we successfully synthesized a nano-flowers FeS/MoS_(2) composite derived from polyoxometalates(NH_(4))_(3)[Fe(III)Mo_(6)O_(24)H_(6)]⋅6H_(2)O(denoted as FeMo6)as the bimetallic precursors.This synthesis strategy enhances the interaction between FeS and MoS_(2),thereby facilitating electron transfer.Notably,the introduction of sulfur vacancies in FeS/MoS_(2) exposes additional Mo4t active sites,promoting the redox cycle of Fe^(2+)/Fe^(3+) and accelerating the regeneration of Fe^(2+),which in turn enhances PMS activation.Therefore,a catalytic oxidation system of FeS/MoS_(2)/PMS is presented that primarily relies on SO_(4)^(⋅-)and⋅OH,with ^(1)O_(2) as a supplementary oxidant.This system exhibits exceptional degradation efficiency for p-chlorophenol(4-CP),achieving 100% degradation within 10 min over a wide pH range of 2.4–8.4.The robust performance and wide applicability of FeS/MoS_(2) catalyst make it a promising candidate in advanced oxidation processes(AOPs)for environmental remediation.展开更多
In sulfidic anoxic environments,iron sulfides are widespread solid phases that play an important role in the arsenic(As)biogeochemical cycle.This work investigated the transformation process of FeS-As coprecipitates,t...In sulfidic anoxic environments,iron sulfides are widespread solid phases that play an important role in the arsenic(As)biogeochemical cycle.This work investigated the transformation process of FeS-As coprecipitates,the concurrent behavior,and the speciation of associated As under anoxic conditions.The results showed that FeS-As coprecipitates could convert to greigite and pyrite.The transformation degree of the produced solid phases was dependent upon the pH conditions and initial As species.These results showed that the As mobilization was closely associated with the solid phase transformation.The solid phase transformationwent from disordered mackinawite to crystallinemackinawite,then greigite and finally pyrite.The As in the coprecipitates underwent a process of release,fixation,and release again.Both reduction of As(Ⅴ)and oxidation of As(Ⅲ)were observed in the aqueous and solid phases during reactions.Our study may have important implications for further understanding of As behavior and Fe/S cycling thatmay occur under an anoxic environment more comprehensively.展开更多
Tailoring 1D nanotubes with refined interfacial interactions and optimized adsorption sites presents a highly promising yet challenging strategy for advancing Na/Li-ion batteries(SIBs/LIBs).Herein,the intertwined yard...Tailoring 1D nanotubes with refined interfacial interactions and optimized adsorption sites presents a highly promising yet challenging strategy for advancing Na/Li-ion batteries(SIBs/LIBs).Herein,the intertwined yardlong bean-like Fe_(9)Ni_(9)S_(16)/FeS heterostructures with sulfur vacancies encapsulated in N-doped carbon nanotubes(3 N-Fe_(9)Ni_(9)S_(16)/FeS-3@CNTs)are controllably synthesized through Fe/Ni-catalyzed pyrolysis of dicyandiamide followed by sulfidation strategies.1D nanotubes with robust outer walls and internal cavity structures shorten the diffusion paths of ions/electrons and buffer volume expansion and aggregation of active materials.The Fe_(9)Ni_(9)S_(16)/FeS heterostructure provides a powerful driving force for charge transfer by forming built-in electric fields,optimizing ion adsorption,while the Fe_(9)Ni_(9)S_(16)features a wider interlayer spacing that allows for frequent Na+/Li+insertion and extraction,thereby enhancing the reaction kinetics within the electrode.Driven by these synergistic factors,the 3 N-Fe_(9)Ni_(9)S_(16)/FeS-3@CNTs demonstrates remarkable electrochemical performance,achieving a substantial reversible capacity of up to 682.1mA h g^(−1)for SIBs at 0.1 A g^(−1)and 782.7 mA h g^(−1)for LIBs at 0.5 A g−1,alongside exceptional cycling stability in SIBs,maintaining 78.7%of its capacity after 1500 cycles at 1 A g^(−1)coupling with the ether-based electrolyte.Employing various electrochemical analyses in conjunction with ex-situ characterization techniques and Density Functional Theory(DFT)calculations,the storage mechanisms and phase transition processes are investigated,elucidating the structure-composition-performance relationships.This work paves the way for a new strategy in designing advanced materials with engineered heterostructures and controllable defects for energy conversion and storage devices.展开更多
Achieving an efficient and stable heterogeneous Fenton reaction over a wide pH range is of great significance for wastewater treatment.Here,a pollen-derived biochar catalyst with a unique honeycomb-like structure,coup...Achieving an efficient and stable heterogeneous Fenton reaction over a wide pH range is of great significance for wastewater treatment.Here,a pollen-derived biochar catalyst with a unique honeycomb-like structure,coupled with the dispersion of magnetic Fe_(3)O_(4)/FeS(Fe/S)nanoparticles,was synthesized by simple impregnation precursor,followed by pyrolysis.The prepared Fe/S-biochar catalyst demonstrated outstanding phenol degradation efficiency across a wide pH range,with 98%of which eliminated even under neutral conditions(pH 7.0).The high catalytic activity was due to the multilevel porous structure of pollenderived biochar provided enough active sites and allowed for better electron transfer,then increases oxidation ability to promote the reaction.Moreover,the acid microenvironment formed by SO_(4)^(2-)group from Fe/S composite extended the pH range for Fenton reaction,and S^(2-)facilitated the conversion of≡Fe^(3+)to≡Fe^(2+),resulting in remarkable degradation efficiency.Further,biochar can effectively promote cycling stability by limiting Fe leaching.This work may provide a general strategy for designing 3D framework biochar-based Fe/S catalysts with excellent performance for heterogeneous Fenton reactions.展开更多
Heterojunction catalysts composed of transition metal sulfides exhibited excellent potentials in electrocatalytic water splitting.Herein,we have designed a FeS/Co_(3)S_(4) heterojunction catalyst for hydrogen evolutio...Heterojunction catalysts composed of transition metal sulfides exhibited excellent potentials in electrocatalytic water splitting.Herein,we have designed a FeS/Co_(3)S_(4) heterojunction catalyst for hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)in alkaline water/seawater solution.Three-dimensional nanoarrays were grown on nickel foam,and the successful synthesis of heterojunction endowed excellent activity to the catalyst.In alkaline water/seawater solution,the low overpotentials(at current density of 10 mA/cm^(2))of HER were 120.3 and 135.6 mV and the low overpotentials of OER were 212 and 232 mV,respectively.This work provided an effective method for highly-efficiently electrocatalytic splitting of water via fabrication of heterojunction.展开更多
基金supported by the Science Technology Talents Lifting Project of Hunan Province(No.2022TJ-N16)the Natural Science Foundation of Hunan Province(Nos.2024JJ4022,2023JJ30277,2025JJ60382)+3 种基金the China Postdoctoral Fellowship Program(GZC20233205)the Scientifc Research Fund of Hunan Provincial Education Department,China(No.24B0270)the National Natural Science Foundation of China(No.32201646)the Key Project of Jiangxi Provincial Research and Development Program(No.20243BBI91001).
文摘The development of high-performance transition metal sulfide(TMS)/carbon composites to replace conventional graphite anode remains a critical challenge for advancing lithium-ion batteries(LIBs).In this study,a facile self-sacrifice template method is developed to prepare FeS encapsulated into N,S co-doped carbon(FeS/NSC)composite using melamine-cyanuric acid(MCA)supermolecule as a multifunctional template precursor.The function of MCA supermolecule for material synthesis is explored,revealing its special function as a dispersant,dopant and pore-forming agent.Furthermore,the effect of Fe source dosage on the morphology,structure and composition of the final products is explored.The resultant FeS/NSC-0.1(where 0.1 represents the mass of added Fe source)exhibits the most optimal proportion,characterized by a good dispersion status of FeS within the NSC matrix,effective N,S co-doping and ample porosity.Benefiting from these merits,the FeS/NSC-0.1 anode demonstrates significantly improved cycling stability and rate capability when compared to the counterparts.Undoubtedly,this work offers a universal method to produce advanced transition metal sulfide/carbon composite electrodes for energy storage and conversion systems.
基金financially supported by the Fundamental Research Program of Shanxi Province, China (Nos. 202303021222190, 202203021212243, and 2023L160)the National Natural Science Foundation of China (No. 22202151 and 22209033)the Fundamental Research Program of Shanxi Normal University, China (No. J CYJ2023015)。
文摘Electrocatalytic N_(2)reduction reaction (NRR) has been considered as a promising and alternative strategy for the synthesis of NH_(3),which will contribute to the goal of carbon neutrality and sustainability.However,this process often suffers from the barrier for N_(2)activation and competitive reactions,resulting in poor NH_(3)yield and low Faraday efficiency (FE).Here,we report a two-dimensiona(2D) ultrathin FeS nanosheets with high conductivity through a facile and scalable method under mild condition.The synthesized FeS catalysts can be used as the work electrode in the electrochemical NRR cell with N_(2)-saturated Na_(2)SO_(4)electrolyte.Such a catalyst shows a NH_(3)yield of 9.0μg·h^(-1)·mg^(-1)(corresponding to 1.47×10^(-4)μmol·s^(-1)·cm^(-2)) and a high FE of 12.4%,which significantly outperformed the other most NRR catalysts.The high catalytic performance of FeS can be attributed to the 2D mackinawite structure,which provides a new insight to explore low-cost and high-performance Fe-based electrocatalysts,as well as accelerates the practical application of the NRR.
基金financially supported by the National Natural Science Foundation of China(52063024 and 51868052)the Natural Science Foundation of Jiangxi Province(20192ACBL21046)the National Science Foundation of State Key Laboratory of Structural Chemistry(20160013).
文摘The degradation of organic pollutants in water is a critical environmental challenge.The iron-doped MoS_(2) catalysts have demonstrated potential in activating peroxymonosulfate(PMS)for environmental remediation,but they face challenges such as poor conductivity,limited electron transfer efficiency,and a scarcity of active sites.To address these issues,we successfully synthesized a nano-flowers FeS/MoS_(2) composite derived from polyoxometalates(NH_(4))_(3)[Fe(III)Mo_(6)O_(24)H_(6)]⋅6H_(2)O(denoted as FeMo6)as the bimetallic precursors.This synthesis strategy enhances the interaction between FeS and MoS_(2),thereby facilitating electron transfer.Notably,the introduction of sulfur vacancies in FeS/MoS_(2) exposes additional Mo4t active sites,promoting the redox cycle of Fe^(2+)/Fe^(3+) and accelerating the regeneration of Fe^(2+),which in turn enhances PMS activation.Therefore,a catalytic oxidation system of FeS/MoS_(2)/PMS is presented that primarily relies on SO_(4)^(⋅-)and⋅OH,with ^(1)O_(2) as a supplementary oxidant.This system exhibits exceptional degradation efficiency for p-chlorophenol(4-CP),achieving 100% degradation within 10 min over a wide pH range of 2.4–8.4.The robust performance and wide applicability of FeS/MoS_(2) catalyst make it a promising candidate in advanced oxidation processes(AOPs)for environmental remediation.
基金supported by the National Key Research and Development Program of China(No.2022YFC3701301)the National Natural Science Foundation of China(Nos.42173063 and 42377251)+1 种基金the Youth Innovation Promotion Association CAS(No.2020200)the Fundamental Research Funds for the Central Universities.
文摘In sulfidic anoxic environments,iron sulfides are widespread solid phases that play an important role in the arsenic(As)biogeochemical cycle.This work investigated the transformation process of FeS-As coprecipitates,the concurrent behavior,and the speciation of associated As under anoxic conditions.The results showed that FeS-As coprecipitates could convert to greigite and pyrite.The transformation degree of the produced solid phases was dependent upon the pH conditions and initial As species.These results showed that the As mobilization was closely associated with the solid phase transformation.The solid phase transformationwent from disordered mackinawite to crystallinemackinawite,then greigite and finally pyrite.The As in the coprecipitates underwent a process of release,fixation,and release again.Both reduction of As(Ⅴ)and oxidation of As(Ⅲ)were observed in the aqueous and solid phases during reactions.Our study may have important implications for further understanding of As behavior and Fe/S cycling thatmay occur under an anoxic environment more comprehensively.
基金supported by the program of National Research Foundation of Korea(NRF)funded by the Ministry of Science,ICT and Future planning(grant number 2022R1A4A1034312,2023R1A2C1007413)by the Commercialization Promotion Agency for R&D Outcomes(COMPA)grant funded by the Korean Government(Ministery of Science and ICT)(RS-2023-00304764)。
文摘Tailoring 1D nanotubes with refined interfacial interactions and optimized adsorption sites presents a highly promising yet challenging strategy for advancing Na/Li-ion batteries(SIBs/LIBs).Herein,the intertwined yardlong bean-like Fe_(9)Ni_(9)S_(16)/FeS heterostructures with sulfur vacancies encapsulated in N-doped carbon nanotubes(3 N-Fe_(9)Ni_(9)S_(16)/FeS-3@CNTs)are controllably synthesized through Fe/Ni-catalyzed pyrolysis of dicyandiamide followed by sulfidation strategies.1D nanotubes with robust outer walls and internal cavity structures shorten the diffusion paths of ions/electrons and buffer volume expansion and aggregation of active materials.The Fe_(9)Ni_(9)S_(16)/FeS heterostructure provides a powerful driving force for charge transfer by forming built-in electric fields,optimizing ion adsorption,while the Fe_(9)Ni_(9)S_(16)features a wider interlayer spacing that allows for frequent Na+/Li+insertion and extraction,thereby enhancing the reaction kinetics within the electrode.Driven by these synergistic factors,the 3 N-Fe_(9)Ni_(9)S_(16)/FeS-3@CNTs demonstrates remarkable electrochemical performance,achieving a substantial reversible capacity of up to 682.1mA h g^(−1)for SIBs at 0.1 A g^(−1)and 782.7 mA h g^(−1)for LIBs at 0.5 A g−1,alongside exceptional cycling stability in SIBs,maintaining 78.7%of its capacity after 1500 cycles at 1 A g^(−1)coupling with the ether-based electrolyte.Employing various electrochemical analyses in conjunction with ex-situ characterization techniques and Density Functional Theory(DFT)calculations,the storage mechanisms and phase transition processes are investigated,elucidating the structure-composition-performance relationships.This work paves the way for a new strategy in designing advanced materials with engineered heterostructures and controllable defects for energy conversion and storage devices.
基金financially supported by the National Natural Science Foundation of China (Nos.21876139 and 21922606)Yulin Science and Technology Project of China (No.CXY2021-134)。
文摘Achieving an efficient and stable heterogeneous Fenton reaction over a wide pH range is of great significance for wastewater treatment.Here,a pollen-derived biochar catalyst with a unique honeycomb-like structure,coupled with the dispersion of magnetic Fe_(3)O_(4)/FeS(Fe/S)nanoparticles,was synthesized by simple impregnation precursor,followed by pyrolysis.The prepared Fe/S-biochar catalyst demonstrated outstanding phenol degradation efficiency across a wide pH range,with 98%of which eliminated even under neutral conditions(pH 7.0).The high catalytic activity was due to the multilevel porous structure of pollenderived biochar provided enough active sites and allowed for better electron transfer,then increases oxidation ability to promote the reaction.Moreover,the acid microenvironment formed by SO_(4)^(2-)group from Fe/S composite extended the pH range for Fenton reaction,and S^(2-)facilitated the conversion of≡Fe^(3+)to≡Fe^(2+),resulting in remarkable degradation efficiency.Further,biochar can effectively promote cycling stability by limiting Fe leaching.This work may provide a general strategy for designing 3D framework biochar-based Fe/S catalysts with excellent performance for heterogeneous Fenton reactions.
基金supported by the Dean/Opening Project of Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology(2023K001)Taishan Scholars Foundation of Shandong province(TSQN201909058).
文摘Heterojunction catalysts composed of transition metal sulfides exhibited excellent potentials in electrocatalytic water splitting.Herein,we have designed a FeS/Co_(3)S_(4) heterojunction catalyst for hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)in alkaline water/seawater solution.Three-dimensional nanoarrays were grown on nickel foam,and the successful synthesis of heterojunction endowed excellent activity to the catalyst.In alkaline water/seawater solution,the low overpotentials(at current density of 10 mA/cm^(2))of HER were 120.3 and 135.6 mV and the low overpotentials of OER were 212 and 232 mV,respectively.This work provided an effective method for highly-efficiently electrocatalytic splitting of water via fabrication of heterojunction.
