To enhance the electrochemical performance of lithium-ion battery anodes with higher silicon content,it is essential to engineer their microstructure for better lithium-ion transport and mitigated volume change as wel...To enhance the electrochemical performance of lithium-ion battery anodes with higher silicon content,it is essential to engineer their microstructure for better lithium-ion transport and mitigated volume change as well.Herein,we suggest an effective approach to control the micropore structure of silicon oxide(SiO_(x))/artificial graphite(AG)composite electrodes using a perforated current collector.The electrode features a unique pore structure,where alternating high-porosity domains and low-porosity domains markedly reduce overall electrode resistance,leading to a 20%improvement in rate capability at a 5C-rate discharge condition.Using microstructure-resolved modeling and simulations,we demonstrate that the patterned micropore structure enhances lithium-ion transport,mitigating the electrolyte concentration gradient of lithium-ion.Additionally,perforating current collector with a chemical etching process increases the number of hydrogen bonding sites and enlarges the interface with the SiO_(x)/AG composite electrode,significantly improving adhesion strength.This,in turn,suppresses mechanical degradation and leads to a 50%higher capacity retention.Thus,regularly arranged micropore structure enabled by the perforated current collector successfully improves both rate capability and cycle life in SiO_(x)/AG composite electrodes,providing valuable insights into electrode engineering.展开更多
Controllable synthesis of ultrathin metallene nanosheets and rational design of their spatial arrangement in favor of electrochemical catalysis are critical for their renewable energy applications.Here,a biomimetic de...Controllable synthesis of ultrathin metallene nanosheets and rational design of their spatial arrangement in favor of electrochemical catalysis are critical for their renewable energy applications.Here,a biomimetic design of“Trunk-Branch-Leaf”strategy is proposed to prepare the ultrathin edge-riched Zn-ene“leaves”with a thickness of~2.5 nm,adjacent Zn-ene cross-linked with each other,which are supported by copper nanoneedle“branches”on copper mesh“trunks,”named as Zn-ene/Cu-CM.The resulting superstructure enables the formation of an interconnected network and multiple channels,which can be used as an electrocatalytic CO_(2) reduction reaction(CO_(2)RR)electrode to allow a fast charge and mass transfer as well as a large electrolyte reservoir.By virtue of the distinctive structure,the obtained Zn-ene/Cu-CM electrode exhibits excellent selectivity and activity toward CO production with a maximum Faradaic efficiency of 91.3%and incredible partial current density up to 40 mA cm^(−2),outperforming most of the state-of-the-art Zn-based electrodes for CO_(2) reduction.The phenolphthalein color probe combined with in situ attenuated total reflection-infrared spectroscopy uncovered the formation of the localized pseudo-alkaline microenvironment at the interface of the Zn-ene/Cu-CM electrode.Theoretical calculations confirmed that the localized pH as the origin is responsible for the adsorption of CO_(2) at the interface and the generation of *COOH and *CO intermediates.This study offers valuable insights into developing efficient electrodes through synergistic regulation of reaction microenvironments and active sites,thereby facilitating the electrolysis of practical CO_(2) conversion.展开更多
Layered oxides have attracted significant attention as cathodes for sodium-ion batteries(SIBs)due to their compositional versatility and tuneable electrochemical performance.However,these materials still face challeng...Layered oxides have attracted significant attention as cathodes for sodium-ion batteries(SIBs)due to their compositional versatility and tuneable electrochemical performance.However,these materials still face challenges such as structural phase transitions,Na^(+)/vacancy ordering,and Jahn–Teller distortion effect,resulting in severe capacity decay and sluggish ion kinetics.We develop a novel Cu/Y dual-doping strategy that leads to the formation of"Na–Y"interlayer aggregates,which act as structural pillars within alkali metal layers,enhancing structural stability and disrupting the ordered arrangement of Na^(+)/vacancies.This disruption leads to a unique coexistence of ordered and disordered Na^(+)/vacancy states with near-zero strain,which significantly improves Na^(+)diffusion kinetics.This structural innovation not only mitigates the unfavorable P2–O2 phase transition but also facilitates rapid ion transport.As a result,the doped material demonstrates exceptional electrochemical performance,including an ultra-long cycle life of 3000 cycles at 10 C and an outstanding high-rate capability of~70 mAh g^(−1)at 50 C.The discovery of this novel interlayer pillar,along with its role in modulating Na^(+)/vacancy arrangements,provides a fresh perspective on engineering layered oxides.It opens up promising new pathways for the structural design of advanced cathode materials toward efficient,stable,and high-rate SIBs.展开更多
Due to the safety,high energy density,and rapid charging feature,aqueous zinc-ion batteries(AZIBs)have attracted great attention in large-scale energy storage systems.Although excellent electrochemical performances ha...Due to the safety,high energy density,and rapid charging feature,aqueous zinc-ion batteries(AZIBs)have attracted great attention in large-scale energy storage systems.Although excellent electrochemical performances have been achieved,the cycling stabilities of AZIBs are still unsatisfactory,especially at low current densities,because the cathode materials are prone to being dissolved into electrolytes.Here we develop a unique zincophilic and hydrophobic amorphous additive of ZnSnO_(3)(ZSO),which effectively prevents the irreversible dissolution and deamination of NH_(4)V_(4)O_(10)(NVO)cathode.Benefiting from the ingenious design,NVO@ZSO cathode delivers the best cycling stability at a low current density(0.1 A·g^(-1)),with an ultrahigh capacity retention of 98.8% after 300 cycles.Besides,at a high current density of 5 A·g^(-1),the NVO@ZSO cathode still possesses excellent cycling performance,and a reversible capacity of 284.6 mAh·g^(-1)is achieved even after 7000 cycles.The mechanism is clarified with the aid of density function theory calculations and molecular dynamics simulations.These findings provide a new paradigm for designing stable cathodes by introducing amorphous additive,which should promote further application exploration of AZIBs at low current densities.展开更多
The major reason of Al anode activation is that Ga can plate out on the aluminum surface and form activated points. The Al-Sn, Al - Ga binary alloys can’t be activat6d in alkaline medium. During the dissolution of th...The major reason of Al anode activation is that Ga can plate out on the aluminum surface and form activated points. The Al-Sn, Al - Ga binary alloys can’t be activat6d in alkaline medium. During the dissolution of the Al - Sn - Ga ternary anode, Sn and Ga dissolove solution aions as ions. After Sn ions deposit on the surface of Al anode, Ga ions will underpotentially deposit on Sn. The higher activation of the polycomponent alloy anode is caused by much more new activated points being continually formed. The activation mechanism for the polycomponent Al-alloy anode in alkaline medium is abided by the" di ssolution-deposition".展开更多
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIT)(No.NRF-2021M3H4A1A02048529)the Ministry of Trade,Industry and Energy(MOTIE)of the Korean government under grant No.RS-2022-00155854support from the DGIST Supercomputing and Big Data Center.
文摘To enhance the electrochemical performance of lithium-ion battery anodes with higher silicon content,it is essential to engineer their microstructure for better lithium-ion transport and mitigated volume change as well.Herein,we suggest an effective approach to control the micropore structure of silicon oxide(SiO_(x))/artificial graphite(AG)composite electrodes using a perforated current collector.The electrode features a unique pore structure,where alternating high-porosity domains and low-porosity domains markedly reduce overall electrode resistance,leading to a 20%improvement in rate capability at a 5C-rate discharge condition.Using microstructure-resolved modeling and simulations,we demonstrate that the patterned micropore structure enhances lithium-ion transport,mitigating the electrolyte concentration gradient of lithium-ion.Additionally,perforating current collector with a chemical etching process increases the number of hydrogen bonding sites and enlarges the interface with the SiO_(x)/AG composite electrode,significantly improving adhesion strength.This,in turn,suppresses mechanical degradation and leads to a 50%higher capacity retention.Thus,regularly arranged micropore structure enabled by the perforated current collector successfully improves both rate capability and cycle life in SiO_(x)/AG composite electrodes,providing valuable insights into electrode engineering.
基金supports of the National Natural Science Foundation of China(NSFC)(52021004,52394202)key project of the Joint Fund for Innovation and Development of Chongqing Natural Science Foundation(CSTB2022NSCQ-LZX0013)+1 种基金the National Natural Science Foundation of China(NSFC)(52301232,and 52476056)the Natural Science Foundation of Chongqing Province(2024NSCQ-MSX1109).
文摘Controllable synthesis of ultrathin metallene nanosheets and rational design of their spatial arrangement in favor of electrochemical catalysis are critical for their renewable energy applications.Here,a biomimetic design of“Trunk-Branch-Leaf”strategy is proposed to prepare the ultrathin edge-riched Zn-ene“leaves”with a thickness of~2.5 nm,adjacent Zn-ene cross-linked with each other,which are supported by copper nanoneedle“branches”on copper mesh“trunks,”named as Zn-ene/Cu-CM.The resulting superstructure enables the formation of an interconnected network and multiple channels,which can be used as an electrocatalytic CO_(2) reduction reaction(CO_(2)RR)electrode to allow a fast charge and mass transfer as well as a large electrolyte reservoir.By virtue of the distinctive structure,the obtained Zn-ene/Cu-CM electrode exhibits excellent selectivity and activity toward CO production with a maximum Faradaic efficiency of 91.3%and incredible partial current density up to 40 mA cm^(−2),outperforming most of the state-of-the-art Zn-based electrodes for CO_(2) reduction.The phenolphthalein color probe combined with in situ attenuated total reflection-infrared spectroscopy uncovered the formation of the localized pseudo-alkaline microenvironment at the interface of the Zn-ene/Cu-CM electrode.Theoretical calculations confirmed that the localized pH as the origin is responsible for the adsorption of CO_(2) at the interface and the generation of *COOH and *CO intermediates.This study offers valuable insights into developing efficient electrodes through synergistic regulation of reaction microenvironments and active sites,thereby facilitating the electrolysis of practical CO_(2) conversion.
基金supported by the“Pioneer”and“Leading Goose”R&D Program of Zhejiang Province of China(No.2024C01056)。
文摘Layered oxides have attracted significant attention as cathodes for sodium-ion batteries(SIBs)due to their compositional versatility and tuneable electrochemical performance.However,these materials still face challenges such as structural phase transitions,Na^(+)/vacancy ordering,and Jahn–Teller distortion effect,resulting in severe capacity decay and sluggish ion kinetics.We develop a novel Cu/Y dual-doping strategy that leads to the formation of"Na–Y"interlayer aggregates,which act as structural pillars within alkali metal layers,enhancing structural stability and disrupting the ordered arrangement of Na^(+)/vacancies.This disruption leads to a unique coexistence of ordered and disordered Na^(+)/vacancy states with near-zero strain,which significantly improves Na^(+)diffusion kinetics.This structural innovation not only mitigates the unfavorable P2–O2 phase transition but also facilitates rapid ion transport.As a result,the doped material demonstrates exceptional electrochemical performance,including an ultra-long cycle life of 3000 cycles at 10 C and an outstanding high-rate capability of~70 mAh g^(−1)at 50 C.The discovery of this novel interlayer pillar,along with its role in modulating Na^(+)/vacancy arrangements,provides a fresh perspective on engineering layered oxides.It opens up promising new pathways for the structural design of advanced cathode materials toward efficient,stable,and high-rate SIBs.
基金supported by the National Natural Science Foundation of China(Nos.U24A2055 and 92164103)the National Key R&D Program of China(No.2021YFA1200800)+2 种基金the Natural Science Foundation of Hubei Province(No.2024AFA052)Wuhan Science and Technology Bureau(Knowledge Innovation Program of Wuhan-Basic Research,No.2023010201010067)the Fundamental Research Funds for the Central Universities(No.2042023kf0187).
文摘Due to the safety,high energy density,and rapid charging feature,aqueous zinc-ion batteries(AZIBs)have attracted great attention in large-scale energy storage systems.Although excellent electrochemical performances have been achieved,the cycling stabilities of AZIBs are still unsatisfactory,especially at low current densities,because the cathode materials are prone to being dissolved into electrolytes.Here we develop a unique zincophilic and hydrophobic amorphous additive of ZnSnO_(3)(ZSO),which effectively prevents the irreversible dissolution and deamination of NH_(4)V_(4)O_(10)(NVO)cathode.Benefiting from the ingenious design,NVO@ZSO cathode delivers the best cycling stability at a low current density(0.1 A·g^(-1)),with an ultrahigh capacity retention of 98.8% after 300 cycles.Besides,at a high current density of 5 A·g^(-1),the NVO@ZSO cathode still possesses excellent cycling performance,and a reversible capacity of 284.6 mAh·g^(-1)is achieved even after 7000 cycles.The mechanism is clarified with the aid of density function theory calculations and molecular dynamics simulations.These findings provide a new paradigm for designing stable cathodes by introducing amorphous additive,which should promote further application exploration of AZIBs at low current densities.
文摘The major reason of Al anode activation is that Ga can plate out on the aluminum surface and form activated points. The Al-Sn, Al - Ga binary alloys can’t be activat6d in alkaline medium. During the dissolution of the Al - Sn - Ga ternary anode, Sn and Ga dissolove solution aions as ions. After Sn ions deposit on the surface of Al anode, Ga ions will underpotentially deposit on Sn. The higher activation of the polycomponent alloy anode is caused by much more new activated points being continually formed. The activation mechanism for the polycomponent Al-alloy anode in alkaline medium is abided by the" di ssolution-deposition".
