Electronic engineering of gallium nitride(Ga N) is critical for enhancement of its electrode performance.In this work, copper(Cu) cation substituted Ga N(Cu-Ga N) nanowires were fabricated to understand the electronic...Electronic engineering of gallium nitride(Ga N) is critical for enhancement of its electrode performance.In this work, copper(Cu) cation substituted Ga N(Cu-Ga N) nanowires were fabricated to understand the electronically engineered electrochemical performance for Li ion storage. Cu cation substitution was revealed at atomic level by combination of X-ray photoelectron spectroscopy(XPS), X-ray absorption fine structure(XAFS), density functional theory(DFT) simulation, and so forth. The Cu-Ga N electrode delivered high capacity of 813.2 m A h g^(-1) at 0.1 A g^(-1) after 200 cycles, increased by 66% relative to the unsubstituted Ga N electrode. After 2000 cycles at 10 A g^(-1),the reversible capacity was still maintained at326.7 m A h g^(-1). The DFT calculations revealed that Cu substitution introduced the impurity electronic states and efficient interatomic electron migration, which can enhance the charge transfer efficiency and reduce the Li ion adsorption energy on the Cu-Ga N electrode. The ex-situ SEM, TEM, HRTEM, and SAED analyses demonstrated the reversible intercalation Li ion storage mechanism and good structural stability. The concept of atomic-arrangement-assisted electronic engineering strategy is anticipated to open up opportunities for advanced energy storage applications.展开更多
Electrochemically active metal anodes,such as lithium,sodium,potassium,and zinc,have attracted great research interests in the advanced rechargeable batteries owing to their superior theoretical energy densities.Unfor...Electrochemically active metal anodes,such as lithium,sodium,potassium,and zinc,have attracted great research interests in the advanced rechargeable batteries owing to their superior theoretical energy densities.Unfortunately,the metal anodes suffer from the huge volume changes with loss of active materials during the plating and stripping processes,resulting in fast capacity decay.Moreover,the random growth of dendrites on the metal anodes will penetrate the separator,causing severe safety issues.Engineering metal anodes by introducing the 2D materials are widely investigated to alleviate these issues.Benefitting from the ultrathin structure feature and unique electrical properties,2D materials are regarded as one of the best host of metal anodes.Besides,the tunable active sites on basal plane enable 2D materials to achieve favorable interaction with metal anodes.Moreover,some 2D materials exhibit good mechanical strength and flexibility,serving as building block for the artificial solid electrolyte interphase.In this review,we mainly disclosed the correlations between the intrinsic properties of 2D materials and their functions in guiding uniform nucleation,controlling the growth of metals,and accommodating the volume change.Also,the challenges of 2D materials in metal anodes are well discussed.Finally,the future directions to develop highperformance metal anodes by taking advantage of these unique features of 2D materials are proposed.展开更多
In past decades,high-entropy(HE)materials,containing five or more elements with approximately equal atomic ratio,are extensively investigated due to their desirable properties in a series of applications.Recently,HE t...In past decades,high-entropy(HE)materials,containing five or more elements with approximately equal atomic ratio,are extensively investigated due to their desirable properties in a series of applications.Recently,HE two-dimensional(2D)materials have become promising materials,which not only endow the advantages from their bulk form but also exhibit unusual properties due to their 2D features.So far,the HE 2D transition metal carbides(MXenes),dichalcogenides(TMDs),hydrotalcites(LDHs),and oxides have been successfully synthesized and performed well in different electrochemical reactions,which is originated from the synergistic effect of multicomponents and atomic thin characteristics.Here,the challenges on processing,characterization,and property predictions of HE 2D materials are emphasized.Finally,viable strategies,advanced processing,fundamental understanding,in-depth characterization of new HE 2D materials are proposed.展开更多
In this study,we developed a novel confinement-synthesis approach to layered double hydroxide nanodots(LDH-NDs)anchored on carbon nanoparticles,which formed a three-dimensional(3D)interconnected network within a porou...In this study,we developed a novel confinement-synthesis approach to layered double hydroxide nanodots(LDH-NDs)anchored on carbon nanoparticles,which formed a three-dimensional(3D)interconnected network within a porous carbon support derived from pyrolysis of metal-organic frameworks(C-MOF).The resultant LDH-NDs@C-MOF nonprecious metal catalysts were demonstrated to exhibit super-high catalytic performance for oxygen evolution reaction(OER)with excellent operation stability and low overpotential(-230 mV)at an exchange current density of 10 mA·cm^(-2).The observed overpotential for the LDH-NDs@C-MOF is much lower than that of large-sized LDH nanosheets(321 mV),pure carbonized MOF(411 mV),and even commercial RuO_(2)(281 mV).X-ray absorption measurements and density functional theory(DFT)calculations revealed partial charge transfer from Fe^(3+)through an O bridge to Ni^(2+)at the edge of LDH-NDs supported by C-MOF to produce the optimal binding energies for OER intermediates.This,coupled with a large number of exposed active sides and efficient charge and electrolyte/reactant/product transports associated with the porous 3D C-MOF support,significantly boosted the OER performance of the LDH-ND catalyst with respect to its nanosheet counterpart.Apart from the fact that this is the first active side identification for LDH-ND OER catalysts,this work provides a general strategy to enhance activities of nanosheet catalysts by converting them into edge-rich nanodots to be supported by 3D porous carbon architectures.展开更多
Coupling low-grade heat(LGH)with salinity gradient is an effective approach to increase the efficiency of the nanofluidic-membrane-based power generator.However,it is a challenge to fabricate membranes with high charg...Coupling low-grade heat(LGH)with salinity gradient is an effective approach to increase the efficiency of the nanofluidic-membrane-based power generator.However,it is a challenge to fabricate membranes with high charge density that ensures ion permselectivity,while maintaining chemical and mechanical stability in this composite environment.Here,we develop a bis[2-(methacryloyloxy)ethyl]phosphate(BMAP)hydrogel membrane with good thermal stability and anti-swelling property through self-crosslinking of the selected monomer.By taking advantage of negative space charge and three-dimensional(3D)interconnected nanochannels,salinity gradient energy conversion efficiency is substantially enhanced by temperature difference.Theoretical and experimental results verify that LGH can largely weaken the concentration polarization,promoting transmembrane ion transport.As a result,such a hydrogel membrane delivers high-performance energy conversion with a power density of 11.53 W·m^(−2)under a negative temperature difference(NTD),showing a 193%increase compared with that without NTD.展开更多
基金supported by the National Natural Science Foundation of China(51672144,51572137,5170218121905152,52072196,52002199,52002200)the Major Basic Research Program of Natural Science Foundation of Shandong Province(ZR2020ZD09)+5 种基金the Shandong Provincial Key Research and Development Program(SPKR&DP)(2019GGX102055)the Natural Science Foundation of Shandong Province(ZR2019BEM042 ZR2020QE063,ZR2020MB045)the Innovation and Technology Program of Shandong Province(2020KJA004)the Innovation Pilot Project of Integration of Science,Education and Industry of Shandong Province(2020KJC-CG04)the Guangdong Basic and Applied Basic Research Foundation(019A15151109332020A1515111086,2020A1515110219)the Shandong Provincial Universities Young Innovative Talent Incubation ProgramInorganic Non-metallic Materials Research and Innovation Team,and Taishan Scholars Program of Shandong Province(ts201511034)。
文摘Electronic engineering of gallium nitride(Ga N) is critical for enhancement of its electrode performance.In this work, copper(Cu) cation substituted Ga N(Cu-Ga N) nanowires were fabricated to understand the electronically engineered electrochemical performance for Li ion storage. Cu cation substitution was revealed at atomic level by combination of X-ray photoelectron spectroscopy(XPS), X-ray absorption fine structure(XAFS), density functional theory(DFT) simulation, and so forth. The Cu-Ga N electrode delivered high capacity of 813.2 m A h g^(-1) at 0.1 A g^(-1) after 200 cycles, increased by 66% relative to the unsubstituted Ga N electrode. After 2000 cycles at 10 A g^(-1),the reversible capacity was still maintained at326.7 m A h g^(-1). The DFT calculations revealed that Cu substitution introduced the impurity electronic states and efficient interatomic electron migration, which can enhance the charge transfer efficiency and reduce the Li ion adsorption energy on the Cu-Ga N electrode. The ex-situ SEM, TEM, HRTEM, and SAED analyses demonstrated the reversible intercalation Li ion storage mechanism and good structural stability. The concept of atomic-arrangement-assisted electronic engineering strategy is anticipated to open up opportunities for advanced energy storage applications.
基金financialy supported by the National Natural Science Foundation of China (grant number,52072014, 52002012)the financial support from China Postdoctoral Science Foundation (2020M670090 and 2020TQ0022)National Postdoctoral Program for Innovative Talents (BX20200027 and BX20200037)
文摘Electrochemically active metal anodes,such as lithium,sodium,potassium,and zinc,have attracted great research interests in the advanced rechargeable batteries owing to their superior theoretical energy densities.Unfortunately,the metal anodes suffer from the huge volume changes with loss of active materials during the plating and stripping processes,resulting in fast capacity decay.Moreover,the random growth of dendrites on the metal anodes will penetrate the separator,causing severe safety issues.Engineering metal anodes by introducing the 2D materials are widely investigated to alleviate these issues.Benefitting from the ultrathin structure feature and unique electrical properties,2D materials are regarded as one of the best host of metal anodes.Besides,the tunable active sites on basal plane enable 2D materials to achieve favorable interaction with metal anodes.Moreover,some 2D materials exhibit good mechanical strength and flexibility,serving as building block for the artificial solid electrolyte interphase.In this review,we mainly disclosed the correlations between the intrinsic properties of 2D materials and their functions in guiding uniform nucleation,controlling the growth of metals,and accommodating the volume change.Also,the challenges of 2D materials in metal anodes are well discussed.Finally,the future directions to develop highperformance metal anodes by taking advantage of these unique features of 2D materials are proposed.
基金National Natural Science Foundation of China,Grant/Award Numbers:52125207,52072014,52102203Beijing Natural Science Foundation,Grant/Award Number:JQ20011+1 种基金China Postdoctoral Science Foundation,Grant/Award Numbers:2021M700008,2021M700316,2020TQ0022National Postdoctoral Program for Innovative Talents,Grant/Award Numbers:BX20200027,BX20200037。
文摘In past decades,high-entropy(HE)materials,containing five or more elements with approximately equal atomic ratio,are extensively investigated due to their desirable properties in a series of applications.Recently,HE two-dimensional(2D)materials have become promising materials,which not only endow the advantages from their bulk form but also exhibit unusual properties due to their 2D features.So far,the HE 2D transition metal carbides(MXenes),dichalcogenides(TMDs),hydrotalcites(LDHs),and oxides have been successfully synthesized and performed well in different electrochemical reactions,which is originated from the synergistic effect of multicomponents and atomic thin characteristics.Here,the challenges on processing,characterization,and property predictions of HE 2D materials are emphasized.Finally,viable strategies,advanced processing,fundamental understanding,in-depth characterization of new HE 2D materials are proposed.
基金supported by The ARC(Nos.DP190103881 and FL190100126).
文摘In this study,we developed a novel confinement-synthesis approach to layered double hydroxide nanodots(LDH-NDs)anchored on carbon nanoparticles,which formed a three-dimensional(3D)interconnected network within a porous carbon support derived from pyrolysis of metal-organic frameworks(C-MOF).The resultant LDH-NDs@C-MOF nonprecious metal catalysts were demonstrated to exhibit super-high catalytic performance for oxygen evolution reaction(OER)with excellent operation stability and low overpotential(-230 mV)at an exchange current density of 10 mA·cm^(-2).The observed overpotential for the LDH-NDs@C-MOF is much lower than that of large-sized LDH nanosheets(321 mV),pure carbonized MOF(411 mV),and even commercial RuO_(2)(281 mV).X-ray absorption measurements and density functional theory(DFT)calculations revealed partial charge transfer from Fe^(3+)through an O bridge to Ni^(2+)at the edge of LDH-NDs supported by C-MOF to produce the optimal binding energies for OER intermediates.This,coupled with a large number of exposed active sides and efficient charge and electrolyte/reactant/product transports associated with the porous 3D C-MOF support,significantly boosted the OER performance of the LDH-ND catalyst with respect to its nanosheet counterpart.Apart from the fact that this is the first active side identification for LDH-ND OER catalysts,this work provides a general strategy to enhance activities of nanosheet catalysts by converting them into edge-rich nanodots to be supported by 3D porous carbon architectures.
基金supported by the National Key R&D Program of China(Nos.2022YFB3805904,2022YFB3805900,and 2020YFA0710401)the National Natural Science Foundation of China(Nos.22122207,21988102,and 52075138)+2 种基金CAS Key Laboratory of Bio-inspired Materials and Interfacial Science,Technical Institute of Physics and Chemistry(No.BMIS202102)China Postdoctoral Science Foundation(Nos.2022TQ0345,2022M723229,and 2022M713226)Postdoctoral International Exchange Talent-Introducing Program(No.YJ20220199).
文摘Coupling low-grade heat(LGH)with salinity gradient is an effective approach to increase the efficiency of the nanofluidic-membrane-based power generator.However,it is a challenge to fabricate membranes with high charge density that ensures ion permselectivity,while maintaining chemical and mechanical stability in this composite environment.Here,we develop a bis[2-(methacryloyloxy)ethyl]phosphate(BMAP)hydrogel membrane with good thermal stability and anti-swelling property through self-crosslinking of the selected monomer.By taking advantage of negative space charge and three-dimensional(3D)interconnected nanochannels,salinity gradient energy conversion efficiency is substantially enhanced by temperature difference.Theoretical and experimental results verify that LGH can largely weaken the concentration polarization,promoting transmembrane ion transport.As a result,such a hydrogel membrane delivers high-performance energy conversion with a power density of 11.53 W·m^(−2)under a negative temperature difference(NTD),showing a 193%increase compared with that without NTD.
