Driven by the burgeoning demand for wearable electronics,the development of inherently safe,mechanically compliant,and high-energy–density power sources has become imperative.Flexible aqueous Zn ions batteries(FAZIBs...Driven by the burgeoning demand for wearable electronics,the development of inherently safe,mechanically compliant,and high-energy–density power sources has become imperative.Flexible aqueous Zn ions batteries(FAZIBs)are hampered by Zn dendrite formation and hydrogen evolution,underscoring the urgent need for highly stable and novel flexible energy-storage devices.Although flexible aqueous cobalt-ion batteries(FACIBs)employing cobalt-salt aqueous electrolytes exhibit high theoretical capacity,they suffer from two limitations:the rapid dissolution of cathode active substances in the aqueous electrolyte and the risk of liquid electrolyte leakage under mechanical deformation.Here,we report the first realization of an ultra-stable,quasi-solid-state and mechanically FACIBs.Polyacrylamide(PAM)containing CoSO4 serves as the quasi-solid electrolyte,while cobalt hexacyanoferrate(CoHCF)functions as the cathode active material,and metallic cobalt foil as the flexible anode.This configuration simultaneously eliminates electrolyte leakage and suppresses the dissolution of CoHCF due to the common-ion effect of Co2+.Consequently,the fabricated FACIBs exhibit extraordinary cycling durability and remarkable mechanical robustness(95.9%retention after 500 bending cycles).Thus,this work provides a new way for designing ultra-stable energy storage devices for wearable electronics.展开更多
Elucidating the structure-activity relationship between the electronic structure of catalytic active sites and oxygen evolution reaction(OER)activity at the orbital level is critical yet challenging in lithium-oxygen(...Elucidating the structure-activity relationship between the electronic structure of catalytic active sites and oxygen evolution reaction(OER)activity at the orbital level is critical yet challenging in lithium-oxygen(Li-O2)batteries.Herein,employing frontier molecular orbital theory,we designed a Pt-based catalyst as a model cathode to investigate the influence of frontier orbital interactions between the Pt dz2 orbital and the 5σorbital of LiO2 on the OER activity.Specifically,compared to the pure Pt catalyst,the dz2-dz2 orbital coupling between low-electronegativity Fe and Pt in PtFe catalyst induces predominant electron transfer from Fe to the dz2 frontier orbital of Pt.As the Pt content in PtFe alloys increases progressively(from Pt58Fe42,Pt67Fe33 to Pt76Fe24),the electron population of the Pt 5dz2 orbital gradually decreases(1.92 for Pt58Fe42,1.85 for Pt67Fe33,and 1.80 for Pt76Fe24).This leads to a gradual enhancement in the strength of interactions between the Pt dz2 orbital and the frontier orbitals of LiO2,consequently resulting in a progressive decline in the OER catalytic activity.Establishing the correlating between the electron population in the dz2 frontier orbital and OER activity provides a descriptor for designing efficient electrocatalysts in Li-O2 batteries.展开更多
基金supported by the National Natural Science Foundation of China(52402040 and 52561160149)National Key R&D Program of China(2024YFE0109200)+7 种基金Fundamental Research Funds for the Central Universities(2024300440)Open Project(M37033)of National Laboratory of Solid State Microstructures,Nanjing UniversityGuangdong Basic and Applied Basic Research Foundation(2025A1515011098)Shenzhen Science and Technology Program(JCYJ20250604190115021)Key Research Project of Universities in Henan Province(25A430006)Henan Province University Students Innovation Training Project(202510479001)Funded by the Training Program for Young Backbone Teachers in Higher Education Institutions of Henan Province(Prof.Chaowei Li)Science and Technology Research Project of Henan Province(242102240076)。
摘要Driven by the burgeoning demand for wearable electronics,the development of inherently safe,mechanically compliant,and high-energy–density power sources has become imperative.Flexible aqueous Zn ions batteries(FAZIBs)are hampered by Zn dendrite formation and hydrogen evolution,underscoring the urgent need for highly stable and novel flexible energy-storage devices.Although flexible aqueous cobalt-ion batteries(FACIBs)employing cobalt-salt aqueous electrolytes exhibit high theoretical capacity,they suffer from two limitations:the rapid dissolution of cathode active substances in the aqueous electrolyte and the risk of liquid electrolyte leakage under mechanical deformation.Here,we report the first realization of an ultra-stable,quasi-solid-state and mechanically FACIBs.Polyacrylamide(PAM)containing CoSO4 serves as the quasi-solid electrolyte,while cobalt hexacyanoferrate(CoHCF)functions as the cathode active material,and metallic cobalt foil as the flexible anode.This configuration simultaneously eliminates electrolyte leakage and suppresses the dissolution of CoHCF due to the common-ion effect of Co2+.Consequently,the fabricated FACIBs exhibit extraordinary cycling durability and remarkable mechanical robustness(95.9%retention after 500 bending cycles).Thus,this work provides a new way for designing ultra-stable energy storage devices for wearable electronics.
基金supported by the National Natural Science Foundation of China/RGC Joint Research Scheme(N_CityU156/25)Green Tech Fund(GTF202220105),Guangdong Basic and Applied Basic Research Foundation(2024A1515011008)+4 种基金the Research Grants Council of the Hong Kong Special Administrative Region,China(Project No.PDFS2425-1S03)City University of Hong Kong(CityU9020002,CityU9680374)National Natural Science Foundation of China(52561160149)Natural Science Foundation of Shandong Province(ZR2024QB045)the Shenzhen Research Institute of City University of Hong Kong.
摘要Elucidating the structure-activity relationship between the electronic structure of catalytic active sites and oxygen evolution reaction(OER)activity at the orbital level is critical yet challenging in lithium-oxygen(Li-O2)batteries.Herein,employing frontier molecular orbital theory,we designed a Pt-based catalyst as a model cathode to investigate the influence of frontier orbital interactions between the Pt dz2 orbital and the 5σorbital of LiO2 on the OER activity.Specifically,compared to the pure Pt catalyst,the dz2-dz2 orbital coupling between low-electronegativity Fe and Pt in PtFe catalyst induces predominant electron transfer from Fe to the dz2 frontier orbital of Pt.As the Pt content in PtFe alloys increases progressively(from Pt58Fe42,Pt67Fe33 to Pt76Fe24),the electron population of the Pt 5dz2 orbital gradually decreases(1.92 for Pt58Fe42,1.85 for Pt67Fe33,and 1.80 for Pt76Fe24).This leads to a gradual enhancement in the strength of interactions between the Pt dz2 orbital and the frontier orbitals of LiO2,consequently resulting in a progressive decline in the OER catalytic activity.Establishing the correlating between the electron population in the dz2 frontier orbital and OER activity provides a descriptor for designing efficient electrocatalysts in Li-O2 batteries.