Lithium metal anode is one of the ideal anode materials for the next generation of high-energy-density battery systems.Unfortunately,the uneven nucleation of Li leads to dendrite growth and volume changes during cycli...Lithium metal anode is one of the ideal anode materials for the next generation of high-energy-density battery systems.Unfortunately,the uneven nucleation of Li leads to dendrite growth and volume changes during cycling,resulting in poor electrochemical performance and potential safety hazards,which hinder its practical application.In this work,a low-cost chicken-bonederived carbon material(CBC)with a biomimetic structure was designed and synthesized using a simple one-step carbonization method.Combining theoretical calculations and experimental results,the self-doped N and S heteroatoms in CBC are demonstrated to effectively reduce the binding energy with Li atoms and lower the nucleation overpotential.After uniform nucleation,the Li metal grows in a spherical shape without dendrites,which is related to the reduction of the local current density inside the biomimetic crosslinking structure of CBC.Benefiting from this favorable Li growth behavior,the Li@CBC electrode achieves ultra-low nucleation overpotential(15.5 mV at 0.1 mA cm^(−2))and superdense lithium deposition(zero volume expansion rate at a capacity of 2 mAh cm^(−2))without introducing additional lithiophilic sites.The CBC retains a high Coulombic efficiency of over 98%in 479 cycles(1 mA cm^(−2)and 1 mAh cm^(−2))when applied in a half-cell with Li,and shows an excellent rate and cycling performance when applied in a full cell with LiFePO4 as the cathode.展开更多
Lithium metal is a compelling choice as an anode material for high-energy-density batteries,attributed to its elevated theoretical specific energy and low redox potential.Nevertheless,challenges arise due to its susce...Lithium metal is a compelling choice as an anode material for high-energy-density batteries,attributed to its elevated theoretical specific energy and low redox potential.Nevertheless,challenges arise due to its susceptibility to high-volume changes and the tendency for dendritic development during cycling,leading to restricted cycle life and diminished Coulombic efficiency(CE).Here,we innovatively engineered a kind of porous biocarbon to serve as the framework for a lithium metal anode,which boasts a heightened specific surface area and uniformly dispersed ZnO active sites,directly derived from metasequoia cambium.The porous structure efficiently mitigates local current density and alleviates the volume expansion of lithium.Also,incorporating the ZnO lithiophilic site notably reduces the nucleation overpotential to a mere 16 mV,facilitating the deposition of lithium in a compact form.As a result,this innovative material ensures an impressive CE of 98.5%for lithium plating/stripping over 500 cycles,a remarkable cycle life exceeding 1200 h in a Li symmetrical cell,and more than 82%capacity retention ratio after an astonishing 690 cycles in full cells.In all,such a rationally designed Li composite anode effectively mitigates volume change,enhances lithophilicity,and reduces local current density,thereby inhibiting dendrite formation.The preparation of a highperformance lithium anode frame proves the feasibility of using biocarbon in a lithium anode frame.展开更多
The rational design of large-area exposure,nonagglomeration,and longrange dispersion of metal nanoparticles(NPs)in the catalysts is critical for the development of energy storage and conversion systems.Little attentio...The rational design of large-area exposure,nonagglomeration,and longrange dispersion of metal nanoparticles(NPs)in the catalysts is critical for the development of energy storage and conversion systems.Little attention has been focused on modulating and developing catalyst interface contact engineering between a carbon substrate and dispersed metal.Here,a highly dispersed ultrafine ruthenium(Ru)NP strategy by double spatial confinement is proposed,that is,incorporating directed growth of metal–organic framework crystals into a bacterial cellulose templating substrate to integrate their respective merits as an excellent electrocatalytic cathode catalyst for a quasi-solid-state Li–O_(2) battery.The porous carbon matrix with highly dispersed ultrafine Ru NPs is well designed and used as cathode catalysts in a Li–O_(2) battery,demonstrating a high discharge areal capacity of 6.82 mAh cm^(–2) at 0.02 mA cm^(–2),a high-rate capability of 4.93 mAh cm^(–2) at 0.2 mA cm^(–2),and stable discharge/charge cycling for up to 500 cycles(2000 h)with low overpotentials of~1.4 V.This fundamental understanding of the structure–performance relationship demonstrates a new and promising approach to optimize highly efficient cathode catalysts for solid-state Li–O_(2) batteries.展开更多
Although biomass-derived carbon(biochar)has been widely used in the energy field,the relation between the carbonization condition and the physical/chemical property of the product remains elusive.Here,we revealed the ...Although biomass-derived carbon(biochar)has been widely used in the energy field,the relation between the carbonization condition and the physical/chemical property of the product remains elusive.Here,we revealed the carbonization condition's effect on the morphology,surface property,and electrochemical performance of the obtained carbon.An open slit pore structure with shower-puff-like nanoparticles can be obtained by finely tuning the carbonization temperature,and its unique pore structure and surface properties enable the Li–O_(2) battery with cycling longevity(221 cycles with 99.8%Coulombic efficiency at 0.2 mA cm^(−2) and controlled discharge–charge depths of 500 mAh g^(−1))and high capacity(16,334 mAh g^(−1) at 0.02 mA cm^(−2)).This work provides a greater understanding of the mechanism of the biochar carbonization procedure under various pyrolysis conditions,paving the way for future study of energy storage devices.展开更多
基金National Natural Science Foundation of China,Grant/Award Numbers:22179005,92372207。
文摘Lithium metal anode is one of the ideal anode materials for the next generation of high-energy-density battery systems.Unfortunately,the uneven nucleation of Li leads to dendrite growth and volume changes during cycling,resulting in poor electrochemical performance and potential safety hazards,which hinder its practical application.In this work,a low-cost chicken-bonederived carbon material(CBC)with a biomimetic structure was designed and synthesized using a simple one-step carbonization method.Combining theoretical calculations and experimental results,the self-doped N and S heteroatoms in CBC are demonstrated to effectively reduce the binding energy with Li atoms and lower the nucleation overpotential.After uniform nucleation,the Li metal grows in a spherical shape without dendrites,which is related to the reduction of the local current density inside the biomimetic crosslinking structure of CBC.Benefiting from this favorable Li growth behavior,the Li@CBC electrode achieves ultra-low nucleation overpotential(15.5 mV at 0.1 mA cm^(−2))and superdense lithium deposition(zero volume expansion rate at a capacity of 2 mAh cm^(−2))without introducing additional lithiophilic sites.The CBC retains a high Coulombic efficiency of over 98%in 479 cycles(1 mA cm^(−2)and 1 mAh cm^(−2))when applied in a half-cell with Li,and shows an excellent rate and cycling performance when applied in a full cell with LiFePO4 as the cathode.
基金supported by the National Natural Science Foundation of China(22179005,92372207)Fundamental Research Funds for the Central Universities(2022CX01017).
文摘Lithium metal is a compelling choice as an anode material for high-energy-density batteries,attributed to its elevated theoretical specific energy and low redox potential.Nevertheless,challenges arise due to its susceptibility to high-volume changes and the tendency for dendritic development during cycling,leading to restricted cycle life and diminished Coulombic efficiency(CE).Here,we innovatively engineered a kind of porous biocarbon to serve as the framework for a lithium metal anode,which boasts a heightened specific surface area and uniformly dispersed ZnO active sites,directly derived from metasequoia cambium.The porous structure efficiently mitigates local current density and alleviates the volume expansion of lithium.Also,incorporating the ZnO lithiophilic site notably reduces the nucleation overpotential to a mere 16 mV,facilitating the deposition of lithium in a compact form.As a result,this innovative material ensures an impressive CE of 98.5%for lithium plating/stripping over 500 cycles,a remarkable cycle life exceeding 1200 h in a Li symmetrical cell,and more than 82%capacity retention ratio after an astonishing 690 cycles in full cells.In all,such a rationally designed Li composite anode effectively mitigates volume change,enhances lithophilicity,and reduces local current density,thereby inhibiting dendrite formation.The preparation of a highperformance lithium anode frame proves the feasibility of using biocarbon in a lithium anode frame.
基金National Natural Science Foundation of China,Grant/Award Number:22179005National Key Research and Development Program of China,Grant/Award Number:2018YFC1900102。
文摘The rational design of large-area exposure,nonagglomeration,and longrange dispersion of metal nanoparticles(NPs)in the catalysts is critical for the development of energy storage and conversion systems.Little attention has been focused on modulating and developing catalyst interface contact engineering between a carbon substrate and dispersed metal.Here,a highly dispersed ultrafine ruthenium(Ru)NP strategy by double spatial confinement is proposed,that is,incorporating directed growth of metal–organic framework crystals into a bacterial cellulose templating substrate to integrate their respective merits as an excellent electrocatalytic cathode catalyst for a quasi-solid-state Li–O_(2) battery.The porous carbon matrix with highly dispersed ultrafine Ru NPs is well designed and used as cathode catalysts in a Li–O_(2) battery,demonstrating a high discharge areal capacity of 6.82 mAh cm^(–2) at 0.02 mA cm^(–2),a high-rate capability of 4.93 mAh cm^(–2) at 0.2 mA cm^(–2),and stable discharge/charge cycling for up to 500 cycles(2000 h)with low overpotentials of~1.4 V.This fundamental understanding of the structure–performance relationship demonstrates a new and promising approach to optimize highly efficient cathode catalysts for solid-state Li–O_(2) batteries.
基金supported by the National Natural Science Foundation of China(NSFC No.22179005)the BIT Research and Innovation Promoting Project(Grant No.2022YCXY008)supported by Cunzhong Zhang at the Beijing Institute of Technology.
文摘Although biomass-derived carbon(biochar)has been widely used in the energy field,the relation between the carbonization condition and the physical/chemical property of the product remains elusive.Here,we revealed the carbonization condition's effect on the morphology,surface property,and electrochemical performance of the obtained carbon.An open slit pore structure with shower-puff-like nanoparticles can be obtained by finely tuning the carbonization temperature,and its unique pore structure and surface properties enable the Li–O_(2) battery with cycling longevity(221 cycles with 99.8%Coulombic efficiency at 0.2 mA cm^(−2) and controlled discharge–charge depths of 500 mAh g^(−1))and high capacity(16,334 mAh g^(−1) at 0.02 mA cm^(−2)).This work provides a greater understanding of the mechanism of the biochar carbonization procedure under various pyrolysis conditions,paving the way for future study of energy storage devices.
