Introduction of vacancies is a widely practiced method to improve the performance of active materials in differentenergy systems, such as secondary batteries, electrocatalysis, and supercapacitors. Because vacancies c...Introduction of vacancies is a widely practiced method to improve the performance of active materials in differentenergy systems, such as secondary batteries, electrocatalysis, and supercapacitors. Because vacancies can generateabundant localized electrons and unsaturated cations, the incorporation of vacancies will significantly improvethe electrical conductivity, ion migration, and provides additional active sites of energy storage materials. Thisarticle systematically reviews different methods to generate oxygen, nitrogen, or selenium vacancies, and techniques to characterize these vacancies. We summarize the specific roles that vacancies play for the active materials in each type of energy storage devices. Additionally, we provide insights into the research progress andchallenges associated with the future development of vacancies technology in various energy storage systems.展开更多
Li4Ti5O12 is considered as a safe and stable anode material for high-power lithium-ion batteries due to its“zero-strain”characteristic during the charge/discharge.However,the intrinsically low electronic conductivit...Li4Ti5O12 is considered as a safe and stable anode material for high-power lithium-ion batteries due to its“zero-strain”characteristic during the charge/discharge.However,the intrinsically low electronic conductivity leads to a deterioration in highrate performance,impeding its intensive application.Herein,the Li4Ti5O12/rutile TiO2(LTO/RT)heterostructured nanorods with tunable oxide phases have been in-situ fabricated by annealing the electrospun nanofiber precursor.By constructing such a heterostructured interface,the as-prepared sample delivers a high capacity of 160.3 mAh·g–1 at 1 C after 200 cycles,125.5 mAh·g–1 at 10 C after 500 cycles and a superior capacity retention of 90.3%after 1,000 cycles at 30 C,outperforming the heterostructure-free counterparts of pure LTO,RT and the commercial LTO product.Density Functional Theory calculation suggests a possible synergistic effect of the LTO/RT interface that would improve the electronic conductivity and Li-ion diffusion.展开更多
基金supported by the National Natural Science Foundation of China(No.52372176)Sichuan Science and Technology Program(2023YFH0026).
文摘Introduction of vacancies is a widely practiced method to improve the performance of active materials in differentenergy systems, such as secondary batteries, electrocatalysis, and supercapacitors. Because vacancies can generateabundant localized electrons and unsaturated cations, the incorporation of vacancies will significantly improvethe electrical conductivity, ion migration, and provides additional active sites of energy storage materials. Thisarticle systematically reviews different methods to generate oxygen, nitrogen, or selenium vacancies, and techniques to characterize these vacancies. We summarize the specific roles that vacancies play for the active materials in each type of energy storage devices. Additionally, we provide insights into the research progress andchallenges associated with the future development of vacancies technology in various energy storage systems.
基金This work was financially supported by the National Key R&D Program of China(No.2021YFB2401900).
文摘Li4Ti5O12 is considered as a safe and stable anode material for high-power lithium-ion batteries due to its“zero-strain”characteristic during the charge/discharge.However,the intrinsically low electronic conductivity leads to a deterioration in highrate performance,impeding its intensive application.Herein,the Li4Ti5O12/rutile TiO2(LTO/RT)heterostructured nanorods with tunable oxide phases have been in-situ fabricated by annealing the electrospun nanofiber precursor.By constructing such a heterostructured interface,the as-prepared sample delivers a high capacity of 160.3 mAh·g–1 at 1 C after 200 cycles,125.5 mAh·g–1 at 10 C after 500 cycles and a superior capacity retention of 90.3%after 1,000 cycles at 30 C,outperforming the heterostructure-free counterparts of pure LTO,RT and the commercial LTO product.Density Functional Theory calculation suggests a possible synergistic effect of the LTO/RT interface that would improve the electronic conductivity and Li-ion diffusion.
