NiFe-layered double hydroxides(NiFe-LDHs)are among the most promising earth-abundant electrocatalysts for the oxygen evolution reaction(OER)in alkaline media.However,their practical application is hindered by intrinsi...NiFe-layered double hydroxides(NiFe-LDHs)are among the most promising earth-abundant electrocatalysts for the oxygen evolution reaction(OER)in alkaline media.However,their practical application is hindered by intrinsic activity limitations and poor stability,primarily due to the asymmetric adsorption of oxygen intermediates.To overcome this,the binding strength must be synergistically tuned to a moderate level to optimize catalytic performance.Here,we engineered NiFeCoCr LDH through Co doping to enhance electrical conductivity and controlled Cr leaching to introduce cationic vacancies for modulating intermediate binding strength in NiFe LDH.X-ray absorption near-edge structure and extended X-ray absorption fine structure analyses reveal that NiFe-LDH with Co doping and Cr vacancies modulates the Ni oxidation state and local coordination environment,leading to a balanced electronic structure and enhanced structural complexity around the Ni sites.Additionally,these vacancies can trap OH^(-)/H_(2)O species,which can serve as a reservoir for OH^(-) transfer,facilitating the rapid formation of OER intermediates and enhancing catalytic performance at high current densities.As a result,V_(Cr)-NiFeCo LDH achieves 1.6 A cm^(-2)current density at 1.7 V vs.RHE while maintaining stable operation for over 1000 h at 500 mA cm^(-2).Density functional theory(DFT)calculations validate the synergistic effects of Co doping and Cr-induced vacancies on intermediate binding energies and improved OER kinetics.Overall,this work presents a rational design strategy to simultaneously enhance the activity and durability of NiFe-based OER catalysts for their application in high-performance alkaline water electrolysis.展开更多
Artificial photosynthesis of hydrogen peroxide(H_(2)O_(2))from earth-abundant water and oxygen is a sustainable approach,however current photocatalysts suffer from low production rate and solar-to-chemical conversion ...Artificial photosynthesis of hydrogen peroxide(H_(2)O_(2))from earth-abundant water and oxygen is a sustainable approach,however current photocatalysts suffer from low production rate and solar-to-chemical conversion efficiency(<1.5%).Herein,we report that nickelchromium layered double hydroxide with intercalated nitrate(NiCrOOH-NO_(3))and a thickness of~4.4 nm is an efficient photocatalyst,enabling a H_(2)O_(2)production yield of 28.7 mmol g^(-1)h^(-1)under visible light irradiation with3.92%solar-to-chemical conversion efficiency.Experimental and computational studies have revealed an inherent facet-dependent reduction-oxidation reaction behavior and spatial separation of photogenerated electrons and holes.An unexpected role of intercalated nitrate is demonstrated,which promotes excited electron—hole spatial separation and facilitates the electron transfer to oxygen intermediate via delocalization.This work provides understandings in the impact of nanostructure and anion in the design of advanced photocatalysts,paving the way toward practical synthesis of H_(2)O_(2)using fully solar-driven renewable energy.展开更多
High-entropy layered hydroxides(HELHs),an emerging frontier in entropy-stabilized materials derived from layered double hydroxides(LDHs),have captivated attention with their unparalleled tunability,thermodynamic stabi...High-entropy layered hydroxides(HELHs),an emerging frontier in entropy-stabilized materials derived from layered double hydroxides(LDHs),have captivated attention with their unparalleled tunability,thermodynamic stability,and electrochemical performance.The integration of the high-entropy concept into LDHs empowers HELHs to surmount the constraints of conventional materials through compositional diversity,structurally disordered configurations,and synergistic multi-element interactions.This review systematically embarks on their synthesis methodologies,functional mechanisms,and applications in energy conversion/storage and biomedicine.Advanced synthesis strategies,such as plasma-assisted hydrothermal methods,facilitate precise control over HELH architectures while supporting scalable production.HELHs demonstrate superior electrochemical performance in critical reactions,including oxygen evolution reaction,water oxidation,hydrogen evolution,and glucose electrooxidation.Future directions encompass integrating in situ characterization with simulations,leveraging machine learning for composition screening,and expanding HELHs application through interdisciplinary collaborations.This work establishes a comprehensive roadmap for advancing HELHs as next-generation multifunctional platforms for sustainable energy and biomedical technologies.展开更多
NiFe layered double hydroxide(NiFe LDH)has emerged as a promising catalyst for the oxygen evolution reaction(OER);however,its hydrogen evolution reaction(HER)activity remains suboptimal due to unfavorable electronic s...NiFe layered double hydroxide(NiFe LDH)has emerged as a promising catalyst for the oxygen evolution reaction(OER);however,its hydrogen evolution reaction(HER)activity remains suboptimal due to unfavorable electronic structures,particularly the d-electron density of metal sites,which impede water dissociation and lead to poor hydrogen adsorption/desorption capabilities.Herein,we introduce an efficient cooperative d-electron density regulation(CDDR)engineering to comprehensively optimize the delectron density of NiFe LDH by grafting MoO_(x) -modified NiFe LDH nanosheets onto porous nickel particles(PNPs).The PNPs facilitate d-electron density modulation along the edges of the nanosheets,while the MoO_(x) species enable d-electron density modulation across the plane of the nanosheets,thus cooperatively constructing enriched d-electron density in NiFe LDH.Theoretical studies validate the CDDR process and reveal that the enriched d-electron density accelerates water dissociation and optimizes the hydrogen adsorption behavior of NiFe LDH.As a result,the engineered catalyst exhibits significantly improved HER activity,achieving an ultra-low overpotential of 38 mV at 10 mA cm^(-2)in 1 M KOH.Additionally,the CDDR-optimized catalyst also exhibits good OER performance,demonstrating excellent bifunctional performance for overall water splitting in both alkaline freshwater and seawater electrolytes.This work presents a novel CDDR strategy for engineering NiFe LDH into efficient HER catalysts without compromising its OER activity,potentially paving the way for the development of active and robust electrocatalysts for sustainable energy applications.展开更多
A method for the effective in-situ formation of boron-containing Mg-Al layered double hydroxides(LDHs)was developed for boron removal and stabilization.The influence of the B/Al molar ratio and pH on the formation of ...A method for the effective in-situ formation of boron-containing Mg-Al layered double hydroxides(LDHs)was developed for boron removal and stabilization.The influence of the B/Al molar ratio and pH on the formation of Mg-Al-B–LDHs was investigated.Compared with the adsorption method,under a high B/Al ratio,the coprecipitation method increased the boron sorption density from 0.256 to 0.472 of Al.The Toxicity Characteristic Leaching Procedure showed that the boron-coprecipitated LDHs exhibited higher stability than the boron-adsorption LDHs.The synthesized LDH samples were characterized by X-ray diffraction,X-ray photoelectron spectroscopy,and solid-state 11B-NMR.The results showed that boron was effectively incorporated into the LDH structure for the coprecipitation method.Combined with the experimental results,a potential in-situ formation pathway for Mg-Al-B–LDHs was elucidated through density functional theory calculations.The boron tended to directly incorporate into the LDH structure in the coprecipitation method,whereas it was predominantly adsorbed on the LDH surface in the adsorption method.The adsorption energy demonstrated that boron preferentially bonded to Mg^(2+)sites on the surface.The mechanism of boron incorporation in the LDHs for the coprecipitation method involved precipitation of amorphous aluminum hydroxide,layered boehmite transformation,nucleation,and layer stacking.During these processes,boron formed complexes to enhance its stability.Residual boron underwent further reactions with the LDHs,including surface adsorption and ion exchange.These findings provide theoretical insight into the effective removal and long-term immobilization of boron in landfill leachate self-remediation processes.展开更多
Owing to its excellent eco-friendliness and facile water elution properties,aluminum-based lithium adsorbents have attracted a surge of interest for selectively extracting Li^(+)from Salt Lake brines,which account for...Owing to its excellent eco-friendliness and facile water elution properties,aluminum-based lithium adsorbents have attracted a surge of interest for selectively extracting Li^(+)from Salt Lake brines,which account for more than 60%of the global lithium resources.However,structural collapse,facile deactivation during desorption process,and ultra-low actual adsorption capacity limit its further large-scale application,particularly in low-grade sulfate-type brines.Herein,considering its advantages,limitations,and structural features,the structural collapse of the aluminum-based lithium adsorbent was effectively suppressed by the in situ intercalation of VO_(3)^(-)and V_(2)O_(7)^(4-)into the interlayer of[LiAl_(2)(OH)_(6)]^(+).Evidently,the initial adsorption capacity andα_(Mg)^(Li)of as-configured adsorbents powder are 14.96 mg g^(-1) and 192.42 in real sulfate-type West Taijinar Salt Lake brines following NaCl salts removal with 800 mg L^(-1) Li^(+)and 9.56 g L^(-1) SO_(4)^(2-).Furthermore,the initial and retained adsorption capacities of these novel adsorbents granulate in brines after 100 adsorption/desorption cycles are 26.68 and 10.36 mg g^(-1),respectively,which are almost 10 times higher than those of industrially utilized products.Based on experiments and density functional theory calculations,the process and mechanism of anion intercalation control were preliminarily elucidated.Furthermore,research findings indicate that intercalated anions can influence not only interlayer interactions but also the backbone strength of LDH-type adsorbents.This work significantly overcomes the major utilization challenges of aluminum-based lithium adsorbents,thereby enabling the high-efficiency and stable extraction of Li^(+)from low-grade brines,including sulfate-type brines.展开更多
Large-scale hydrogen production via water electrolysis faces a freshwater shortage.Direct seawater electrolysis offers a solution but encounters new challenges.Herein,we report a feasible strategy to both prevent meta...Large-scale hydrogen production via water electrolysis faces a freshwater shortage.Direct seawater electrolysis offers a solution but encounters new challenges.Herein,we report a feasible strategy to both prevent metal hydroxides deposition and boost the hydrogen evolution reaction by adding a chelating agent,EDTA-Na_(4),that chelates with Mg^(2+)/Ca^(2+),thus inhibiting their deposition and gathering them near the cathode surface,resulting in breaking the ordered hydrogen bond networks of interfacial water and reducing the activation energy of water dissociation.Furthermore,hydrolysis of–COO^(-) also promoted water dissociation to produce more active*H and*OH near the electrode surface that in turn serves as a diffusion medium for*OH,accelerating mass transfer and enabling seawater electrolysis to exhibit a stable performance,which operates continuously at 100 mA cm^(-2)@2.20 V and 200 mA cm^(-2)@2.58 V for 400 h in the symmetric electrolyzer and 500 mA cm^(-2)@2.29 V for over 500 h in the asymmetric electrolyzer.This study provides a new perspective to address the issues of stable and scalable direct seawater electrolysis for practical green hydrogen production.展开更多
With exhaustion of fossil fuels and the deterioration of global environment,widespread and intensive researches have been concentrated on clean and sustainable alternative energy sources,such as metal-air batteries[1]...With exhaustion of fossil fuels and the deterioration of global environment,widespread and intensive researches have been concentrated on clean and sustainable alternative energy sources,such as metal-air batteries[1],fuel cells[2]and water splitting devices[3].Electrocatalytic oxidation of water to O2(oxygen evolution reaction,OER)is a vital chemical process involved in energy storage and conversion from renewable sources in form of molecular fuels such as H2 via water electrolysis,which has attracted a great amount of research efforts in the past few years[4,5].Nowadays,RuO2 and IrO2 are widely used as typical excellent OER electrocatalysts.However,their high-cost and scarce nature restricts the broadly commercial application of those materials[6,7].Hence,there is an urgent demand to develop low cost,highly efficient,and superb stable OER catalysts.展开更多
Ternary NiCoFe layer hydroxides with different Ni/Co/Fe molar ratios were prepared using simple urea method.By finely tuning Ni/Co/Fe molar ratio,the optimized hydroxide(LDH(2.0)),a Ni/Co/Fe molar ratio of 2.0/1.0/1.0...Ternary NiCoFe layer hydroxides with different Ni/Co/Fe molar ratios were prepared using simple urea method.By finely tuning Ni/Co/Fe molar ratio,the optimized hydroxide(LDH(2.0)),a Ni/Co/Fe molar ratio of 2.0/1.0/1.0,provided high specific capacitance(408 F g^-1at 2.0 A g^-1)and good stability(90.9%retention over 1000 cycles)due to maximum crystallinity(91.35%crystallinity)and specific surface area(160 m^2g^-1).In order to further improve the electrochemical performances,the LDH(2.0)was made into a composite(LDH/PANI)with polyaniline(PANI)via in situ polymerization of aniline monomer.The LDH/PANI composite had a much higher specific capacitance(717 F g^-1at 2.0 A g^-1)compared with the LDH(2.0),and a significant improvement of cycleability(84.7%retention over 1000 cycles).The results indicated that the LDH/PANI had a synergistic effect of both components due to the complementary properties,which guaranteed a good electric contact and consequently increased the specific capacitance.These provided a new approach for designing organic-inorganic composite materials with potential application in supercapacitors.展开更多
Flexible aqueous Ni//Zn batteries have attracted much attention as promising candidates for energy storage in the field of flexible electronics.However,the Ni-based cathodes still face the challenges of poor conductiv...Flexible aqueous Ni//Zn batteries have attracted much attention as promising candidates for energy storage in the field of flexible electronics.However,the Ni-based cathodes still face the challenges of poor conductivity,confined charge/mass transfer,and non-flexibility.In this work,we designed a hollow tubular structure consisting of a conductive silver nanowire (Ag NW) wrapped by active Ni Co layered double hydroxide (LDH),for enhancing the electrical conductivity,improving the charge/mass transfer kinetics,and facilitating the ion penetration.By optimizing the contents of Ni,Co and Ag NW,the Ni_(4)Co LDH@Ag_(1.5)NW composite shows a maximum specific capacity of 115.83 m Ah g^(-1)at 0.1 A g^(-1)measured in a two-electrode system.Highlightingly,the flexible aqueous Ni//Zn battery assembled by Ni_(4)Co LDH@Ag_(1.5)NW interwoven with multi-walled carbon nanotube cathode and Zn foil anode realizes a high power density of 160μW cm^(-2)at the energy density of 23.14μWh cm^(-2),which is superior compared with those of oxide/hydroxide based devices and even higher than those of many carbon-based supercapacitors,showing its promising potentials for flexible energy storage applications.展开更多
Electrochemical CO_(2)reduction into energy-carrying compounds,such as formate,is of great importance for carbon neutrality,which however suffers from high electrical energy input and liquid products crossover.Herein,...Electrochemical CO_(2)reduction into energy-carrying compounds,such as formate,is of great importance for carbon neutrality,which however suffers from high electrical energy input and liquid products crossover.Herein,we fabricated self-supported ultrathin NiCo layered double hydroxides(LDHs)electrodes as anode for methanol electrooxidation to achieve a high formate production rate(5.89 mmol h^(-1)cm^(-2))coupled with CO_(2)electro-reduction at the cathode.A total formate faradic efficiency of both anode for methanol oxidation and cathode for CO_(2)reduction can reach up to 188%driven by a low cell potential of only 2.06 V at 100 mA cm^(-2)in membrane-electrode assembly(MEA).Physical characterizations demonstrated that Ni^(3+)species,formed on the electrochemical oxidation of Ni-containing hydroxide,acted as catalytically active species for the oxidation of methanol to formate.Furthermore,DFT calculations revealed that ultrathin LDHs were beneficial for the formation of Ni^(3+)in hydroxides and introducing oxygen vacancy in NiCo-LDH could decrease the energy barrier of the rate-determining step for methanol oxidation.This work presents a promising approach for fabricating advanced electrodes towards electrocatalytic reactions.展开更多
基金supported by the Natural Science Foundation of China Grant No.52272289 and 5240223,and JSPS(Japan Society for the Promotion of Science)of Grant No.22K19088,23H00313,24H02202,and 24H02205。
文摘NiFe-layered double hydroxides(NiFe-LDHs)are among the most promising earth-abundant electrocatalysts for the oxygen evolution reaction(OER)in alkaline media.However,their practical application is hindered by intrinsic activity limitations and poor stability,primarily due to the asymmetric adsorption of oxygen intermediates.To overcome this,the binding strength must be synergistically tuned to a moderate level to optimize catalytic performance.Here,we engineered NiFeCoCr LDH through Co doping to enhance electrical conductivity and controlled Cr leaching to introduce cationic vacancies for modulating intermediate binding strength in NiFe LDH.X-ray absorption near-edge structure and extended X-ray absorption fine structure analyses reveal that NiFe-LDH with Co doping and Cr vacancies modulates the Ni oxidation state and local coordination environment,leading to a balanced electronic structure and enhanced structural complexity around the Ni sites.Additionally,these vacancies can trap OH^(-)/H_(2)O species,which can serve as a reservoir for OH^(-) transfer,facilitating the rapid formation of OER intermediates and enhancing catalytic performance at high current densities.As a result,V_(Cr)-NiFeCo LDH achieves 1.6 A cm^(-2)current density at 1.7 V vs.RHE while maintaining stable operation for over 1000 h at 500 mA cm^(-2).Density functional theory(DFT)calculations validate the synergistic effects of Co doping and Cr-induced vacancies on intermediate binding energies and improved OER kinetics.Overall,this work presents a rational design strategy to simultaneously enhance the activity and durability of NiFe-based OER catalysts for their application in high-performance alkaline water electrolysis.
基金support from the National Natural Science Foundation of China(NSFC 21905092,22475072 and 22075085)the Fundamental Research Funds for the Central Universities+1 种基金supported by the Shanghai Frontiers Science Center of Molecule Intelligent SynthesesEast China Normal University Multifunctional Platform for Innovation(004)。
文摘Artificial photosynthesis of hydrogen peroxide(H_(2)O_(2))from earth-abundant water and oxygen is a sustainable approach,however current photocatalysts suffer from low production rate and solar-to-chemical conversion efficiency(<1.5%).Herein,we report that nickelchromium layered double hydroxide with intercalated nitrate(NiCrOOH-NO_(3))and a thickness of~4.4 nm is an efficient photocatalyst,enabling a H_(2)O_(2)production yield of 28.7 mmol g^(-1)h^(-1)under visible light irradiation with3.92%solar-to-chemical conversion efficiency.Experimental and computational studies have revealed an inherent facet-dependent reduction-oxidation reaction behavior and spatial separation of photogenerated electrons and holes.An unexpected role of intercalated nitrate is demonstrated,which promotes excited electron—hole spatial separation and facilitates the electron transfer to oxygen intermediate via delocalization.This work provides understandings in the impact of nanostructure and anion in the design of advanced photocatalysts,paving the way toward practical synthesis of H_(2)O_(2)using fully solar-driven renewable energy.
基金the financial support by Advanced Materials-National Science and Technology Major Project(2024ZD0607400)the National Natural Science Foundation of China(No.52402305)+4 种基金the high-level innovation and entrepreneurship talent project of Qinchuangyuan(No.QCYRCXM-2023-084)the Postdoctoral Fellowship Program of CPSF under Grant Number GZB20230570 and 2024M752552Key projects of Shaanxi Province,China(2023GXLH-001)Natural Science Basic Research Program of Shaanxi(Program No.2024JCYBQN-0494,No.2022TD-27)the State Key Laboratory for Electrical Insulation and Power Equipment(No.EIPE23125)。
文摘High-entropy layered hydroxides(HELHs),an emerging frontier in entropy-stabilized materials derived from layered double hydroxides(LDHs),have captivated attention with their unparalleled tunability,thermodynamic stability,and electrochemical performance.The integration of the high-entropy concept into LDHs empowers HELHs to surmount the constraints of conventional materials through compositional diversity,structurally disordered configurations,and synergistic multi-element interactions.This review systematically embarks on their synthesis methodologies,functional mechanisms,and applications in energy conversion/storage and biomedicine.Advanced synthesis strategies,such as plasma-assisted hydrothermal methods,facilitate precise control over HELH architectures while supporting scalable production.HELHs demonstrate superior electrochemical performance in critical reactions,including oxygen evolution reaction,water oxidation,hydrogen evolution,and glucose electrooxidation.Future directions encompass integrating in situ characterization with simulations,leveraging machine learning for composition screening,and expanding HELHs application through interdisciplinary collaborations.This work establishes a comprehensive roadmap for advancing HELHs as next-generation multifunctional platforms for sustainable energy and biomedical technologies.
基金financially supported from the National Key Research and Development Program of China(2022YFB3803600)the National Natural Science Foundation of China(52301272,22309168,12564025,and 52472205)+7 种基金the Fundamental Research Funds for the Central Universities(CCNU25ZH006)the National College Student Innovation and Entrepreneurship Training Project(202510513082)the Research Program of HBNU(2025X082 and2025Y145)the Foundation of Hubei Key Laboratory of Photoelectric Materials and Devices(PMD202404)the General Program of Open Project of the State Key Laboratory of Precision Welding and Joining of Materials Structures(MSWJ-25M-18)the Key Research Project of Hubei Provincial Department of Education(No.D20252503)the Key Project of Hubei Provincial Natural Science Foundation of China(2025AFD002)the Foundation of National Laboratory of Solid State Microstructures(M37087)。
文摘NiFe layered double hydroxide(NiFe LDH)has emerged as a promising catalyst for the oxygen evolution reaction(OER);however,its hydrogen evolution reaction(HER)activity remains suboptimal due to unfavorable electronic structures,particularly the d-electron density of metal sites,which impede water dissociation and lead to poor hydrogen adsorption/desorption capabilities.Herein,we introduce an efficient cooperative d-electron density regulation(CDDR)engineering to comprehensively optimize the delectron density of NiFe LDH by grafting MoO_(x) -modified NiFe LDH nanosheets onto porous nickel particles(PNPs).The PNPs facilitate d-electron density modulation along the edges of the nanosheets,while the MoO_(x) species enable d-electron density modulation across the plane of the nanosheets,thus cooperatively constructing enriched d-electron density in NiFe LDH.Theoretical studies validate the CDDR process and reveal that the enriched d-electron density accelerates water dissociation and optimizes the hydrogen adsorption behavior of NiFe LDH.As a result,the engineered catalyst exhibits significantly improved HER activity,achieving an ultra-low overpotential of 38 mV at 10 mA cm^(-2)in 1 M KOH.Additionally,the CDDR-optimized catalyst also exhibits good OER performance,demonstrating excellent bifunctional performance for overall water splitting in both alkaline freshwater and seawater electrolytes.This work presents a novel CDDR strategy for engineering NiFe LDH into efficient HER catalysts without compromising its OER activity,potentially paving the way for the development of active and robust electrocatalysts for sustainable energy applications.
基金supported by the research equipment (Nos. G1006,G1010 and G1018) shared in MEXT Project for promoting public utilization of advanced research infrastructure (Program for supporting construction of core facilities)(No. JPMXS0440500023)financial support of the China Scholarship Council.
文摘A method for the effective in-situ formation of boron-containing Mg-Al layered double hydroxides(LDHs)was developed for boron removal and stabilization.The influence of the B/Al molar ratio and pH on the formation of Mg-Al-B–LDHs was investigated.Compared with the adsorption method,under a high B/Al ratio,the coprecipitation method increased the boron sorption density from 0.256 to 0.472 of Al.The Toxicity Characteristic Leaching Procedure showed that the boron-coprecipitated LDHs exhibited higher stability than the boron-adsorption LDHs.The synthesized LDH samples were characterized by X-ray diffraction,X-ray photoelectron spectroscopy,and solid-state 11B-NMR.The results showed that boron was effectively incorporated into the LDH structure for the coprecipitation method.Combined with the experimental results,a potential in-situ formation pathway for Mg-Al-B–LDHs was elucidated through density functional theory calculations.The boron tended to directly incorporate into the LDH structure in the coprecipitation method,whereas it was predominantly adsorbed on the LDH surface in the adsorption method.The adsorption energy demonstrated that boron preferentially bonded to Mg^(2+)sites on the surface.The mechanism of boron incorporation in the LDHs for the coprecipitation method involved precipitation of amorphous aluminum hydroxide,layered boehmite transformation,nucleation,and layer stacking.During these processes,boron formed complexes to enhance its stability.Residual boron underwent further reactions with the LDHs,including surface adsorption and ion exchange.These findings provide theoretical insight into the effective removal and long-term immobilization of boron in landfill leachate self-remediation processes.
基金supported by the Sichuan Provincial Department of Science and Technology Project (2025YFHZ0271).
文摘Owing to its excellent eco-friendliness and facile water elution properties,aluminum-based lithium adsorbents have attracted a surge of interest for selectively extracting Li^(+)from Salt Lake brines,which account for more than 60%of the global lithium resources.However,structural collapse,facile deactivation during desorption process,and ultra-low actual adsorption capacity limit its further large-scale application,particularly in low-grade sulfate-type brines.Herein,considering its advantages,limitations,and structural features,the structural collapse of the aluminum-based lithium adsorbent was effectively suppressed by the in situ intercalation of VO_(3)^(-)and V_(2)O_(7)^(4-)into the interlayer of[LiAl_(2)(OH)_(6)]^(+).Evidently,the initial adsorption capacity andα_(Mg)^(Li)of as-configured adsorbents powder are 14.96 mg g^(-1) and 192.42 in real sulfate-type West Taijinar Salt Lake brines following NaCl salts removal with 800 mg L^(-1) Li^(+)and 9.56 g L^(-1) SO_(4)^(2-).Furthermore,the initial and retained adsorption capacities of these novel adsorbents granulate in brines after 100 adsorption/desorption cycles are 26.68 and 10.36 mg g^(-1),respectively,which are almost 10 times higher than those of industrially utilized products.Based on experiments and density functional theory calculations,the process and mechanism of anion intercalation control were preliminarily elucidated.Furthermore,research findings indicate that intercalated anions can influence not only interlayer interactions but also the backbone strength of LDH-type adsorbents.This work significantly overcomes the major utilization challenges of aluminum-based lithium adsorbents,thereby enabling the high-efficiency and stable extraction of Li^(+)from low-grade brines,including sulfate-type brines.
基金the support from the National Key Research and Development Program of China(2023YFB4005000)the Joint Fund of Liaoning Binhai Laboratory(LBLF-2023-04)+3 种基金Dalian Science and Technology Talent Innovation Support Plan(2022RY09)Innovation Research Fund of Dalian Institute of Chemical Physics(DICP I202318)National Natural Science Foundation of China(22478384)the UK EPSRC(EP/W03784X/1)。
文摘Large-scale hydrogen production via water electrolysis faces a freshwater shortage.Direct seawater electrolysis offers a solution but encounters new challenges.Herein,we report a feasible strategy to both prevent metal hydroxides deposition and boost the hydrogen evolution reaction by adding a chelating agent,EDTA-Na_(4),that chelates with Mg^(2+)/Ca^(2+),thus inhibiting their deposition and gathering them near the cathode surface,resulting in breaking the ordered hydrogen bond networks of interfacial water and reducing the activation energy of water dissociation.Furthermore,hydrolysis of–COO^(-) also promoted water dissociation to produce more active*H and*OH near the electrode surface that in turn serves as a diffusion medium for*OH,accelerating mass transfer and enabling seawater electrolysis to exhibit a stable performance,which operates continuously at 100 mA cm^(-2)@2.20 V and 200 mA cm^(-2)@2.58 V for 400 h in the symmetric electrolyzer and 500 mA cm^(-2)@2.29 V for over 500 h in the asymmetric electrolyzer.This study provides a new perspective to address the issues of stable and scalable direct seawater electrolysis for practical green hydrogen production.
基金financially supported by the National Natural Science Foundation of China(U1707603,21521005,21975013,21901017)the National Key Research and Development Program of China(2017YFA0206500,2018YFA0702000)+2 种基金Beijing Natural Science Foundation(2172042)PetroChina Innovation Foundationthe Fundamental Research Funds for the Central Universities。
文摘With exhaustion of fossil fuels and the deterioration of global environment,widespread and intensive researches have been concentrated on clean and sustainable alternative energy sources,such as metal-air batteries[1],fuel cells[2]and water splitting devices[3].Electrocatalytic oxidation of water to O2(oxygen evolution reaction,OER)is a vital chemical process involved in energy storage and conversion from renewable sources in form of molecular fuels such as H2 via water electrolysis,which has attracted a great amount of research efforts in the past few years[4,5].Nowadays,RuO2 and IrO2 are widely used as typical excellent OER electrocatalysts.However,their high-cost and scarce nature restricts the broadly commercial application of those materials[6,7].Hence,there is an urgent demand to develop low cost,highly efficient,and superb stable OER catalysts.
基金supported financially by the Joint Research Program of Hunan Provincial Natural Science Foundation (Xiangtan) of China (No. 2016JJ5030)the Hunan 2011 Collaborative Innovation Center of Chemical Engineering & Technology with Environmental Benignitythe PhD Startup Foundation of Xiangtan University (No. 17QDZ05)
文摘Ternary NiCoFe layer hydroxides with different Ni/Co/Fe molar ratios were prepared using simple urea method.By finely tuning Ni/Co/Fe molar ratio,the optimized hydroxide(LDH(2.0)),a Ni/Co/Fe molar ratio of 2.0/1.0/1.0,provided high specific capacitance(408 F g^-1at 2.0 A g^-1)and good stability(90.9%retention over 1000 cycles)due to maximum crystallinity(91.35%crystallinity)and specific surface area(160 m^2g^-1).In order to further improve the electrochemical performances,the LDH(2.0)was made into a composite(LDH/PANI)with polyaniline(PANI)via in situ polymerization of aniline monomer.The LDH/PANI composite had a much higher specific capacitance(717 F g^-1at 2.0 A g^-1)compared with the LDH(2.0),and a significant improvement of cycleability(84.7%retention over 1000 cycles).The results indicated that the LDH/PANI had a synergistic effect of both components due to the complementary properties,which guaranteed a good electric contact and consequently increased the specific capacitance.These provided a new approach for designing organic-inorganic composite materials with potential application in supercapacitors.
基金sponsored by the National Natural Science Foundation of China(61804054)the Natural Science Foundation of Shanghai(18ZR1410400)+2 种基金the Shanghai Sailing Program(17YF1403300)the Shanghai Aerospace Science and Technology Innovation Fundation(SISP2018)the Shanghai Aerospace Science and Technology Innovation Fund(SAST2019-067)。
文摘Flexible aqueous Ni//Zn batteries have attracted much attention as promising candidates for energy storage in the field of flexible electronics.However,the Ni-based cathodes still face the challenges of poor conductivity,confined charge/mass transfer,and non-flexibility.In this work,we designed a hollow tubular structure consisting of a conductive silver nanowire (Ag NW) wrapped by active Ni Co layered double hydroxide (LDH),for enhancing the electrical conductivity,improving the charge/mass transfer kinetics,and facilitating the ion penetration.By optimizing the contents of Ni,Co and Ag NW,the Ni_(4)Co LDH@Ag_(1.5)NW composite shows a maximum specific capacity of 115.83 m Ah g^(-1)at 0.1 A g^(-1)measured in a two-electrode system.Highlightingly,the flexible aqueous Ni//Zn battery assembled by Ni_(4)Co LDH@Ag_(1.5)NW interwoven with multi-walled carbon nanotube cathode and Zn foil anode realizes a high power density of 160μW cm^(-2)at the energy density of 23.14μWh cm^(-2),which is superior compared with those of oxide/hydroxide based devices and even higher than those of many carbon-based supercapacitors,showing its promising potentials for flexible energy storage applications.
基金the financial support from the National Nature Science Foundation of China(22078232 and 21938008)the Haihe Laboratory of Sustainable Chemical Transformations for financial support。
文摘Electrochemical CO_(2)reduction into energy-carrying compounds,such as formate,is of great importance for carbon neutrality,which however suffers from high electrical energy input and liquid products crossover.Herein,we fabricated self-supported ultrathin NiCo layered double hydroxides(LDHs)electrodes as anode for methanol electrooxidation to achieve a high formate production rate(5.89 mmol h^(-1)cm^(-2))coupled with CO_(2)electro-reduction at the cathode.A total formate faradic efficiency of both anode for methanol oxidation and cathode for CO_(2)reduction can reach up to 188%driven by a low cell potential of only 2.06 V at 100 mA cm^(-2)in membrane-electrode assembly(MEA).Physical characterizations demonstrated that Ni^(3+)species,formed on the electrochemical oxidation of Ni-containing hydroxide,acted as catalytically active species for the oxidation of methanol to formate.Furthermore,DFT calculations revealed that ultrathin LDHs were beneficial for the formation of Ni^(3+)in hydroxides and introducing oxygen vacancy in NiCo-LDH could decrease the energy barrier of the rate-determining step for methanol oxidation.This work presents a promising approach for fabricating advanced electrodes towards electrocatalytic reactions.
