Layered V_(2)O_(5) cathode holds the merits of high theoretical specific capacity(589 mA h g^(-1))in aqueous zinc-ion batteries(AZIBs),yet it still suffers from inferior bulk conductivity and structure degradation not...Layered V_(2)O_(5) cathode holds the merits of high theoretical specific capacity(589 mA h g^(-1))in aqueous zinc-ion batteries(AZIBs),yet it still suffers from inferior bulk conductivity and structure degradation notably during prolonged cycling.Herein,we ingeniously design cations(Na^(+)/Co^(2+)/Al^(3+))and anion(F^(-))synergistic-doped hydrated V_(2)O_(5)·0.48H_(2)O cathode(VNACOF)to enhance the electronic and spatial effects in the bulk.A range of in-situ,ex-situ characterizations,and DFT calculations profoundly clarify the strengthened ionic/electronic conductivities,structural stability,and Zn^(2+)diffusion kinetics.As a result,the VNACOF displays a superior discharge capacity(529 mA h g^(-1)@0.1 C),rate capabilities(488 mA h g^(-1)@0.5 C,437 mA h g^(-1)@1C),and cycling stability(301 mA h g^(-1)@10 C@5000 cycles@93%)with sufficient energy density(393 W h kg^(-1)),Furthermore,the pouch-cells with high-load(60 mg)also deliver superior cyclic(2 C@178 mA h g^(-1)@1000 cycles@90%)and rate performance(132 mA h g^(-1)@5 C),revealing great application potential for high-energy-density and high-stability AZIBs.展开更多
Aqueous Zn ion batteries(ZIBs)have received extensive attention due to their intrinsic safety,high abundance,and low cost.However,uncontrolled dendrite growth and water-induced side reactions at electrod e/electrolyte...Aqueous Zn ion batteries(ZIBs)have received extensive attention due to their intrinsic safety,high abundance,and low cost.However,uncontrolled dendrite growth and water-induced side reactions at electrod e/electrolyte interfaces hinder the advancement of ZIBs.Herein,density functional theory(DFT)calculation indicates that Zn heptafluorobutyrate can facilitate uniform Zn^(2+)deposition by leveraging the abundant zincophilic groups(e.g.,-COO^(-)and-CF)and inhibit water-induced side reactions due to the presence of hydrophobic carbon chains.A Zn heptafluorobutyrate protective layer(denoted as ZFA)is constructed on the metallic Zn surface in situ by acid etching process to control Zn^(2+)desolvation and nucleation behaviors,ensuring enhanced reversibility and stability of Zn anodes.Consequently,the Zn@ZFA anode demonstrates stable operation for more than 2200 h at 1 mA cm^(-2)and over 7300cycles at 40 mA cm^(-2),with high Coulombic efficiency of 99.8%over 1900 cycles at 5 mA cm^(-2).Impressively,Zn@ZFA‖VO_(2)full cell achieves exceptional cycle life(204 mA h g^(-1)after 750 cycles at 3 A g^(-1))and remarkable rate performance(236 mA g^(-1)at 10 A g^(-1)).This work provides an insightful guidance for constructing a protection layer of dendrite-free Zn anodes for high-performance ZIBs.展开更多
Composite Li metal anodes based on three-dimensional(3D) porous frameworks have been considered as an effective material for achieving stable Li metal batteries with high energy density.However,uneven Li deposition be...Composite Li metal anodes based on three-dimensional(3D) porous frameworks have been considered as an effective material for achieving stable Li metal batteries with high energy density.However,uneven Li deposition behavior still occurs at the top of 3D frameworks owing to the local accumulation of Li ions.To promote uniform Li deposition without top dendrite growth,herein,a layered multifunctional framework based on oxidation-treated polyacrylonitrile(OPAN) and metal-organic framework(MOF) derivatives was proposed for rationally regulating the distribution of Li ions flux,nucleation sites,and electrical conductivity.Profiting from these merits,the OPAN/carbon nano fiber-MOF(CMOF) composite framework demonstrated a reversible Li plating/stripping behavior for 500 cycles with a stable Coulombic efficiency of around 99.0% at the current density of 2 mA/cm~2.Besides,such a Li composite anode exhibited a superior cycle lifespan of over 1300 h under a low polarized voltage of 18 mV in symmetrical cells.When the Li composite anode was paired with LiFePO_(4)(LFP) cathode,the obtained full cell exhibited a stable cycling over 500 cycles.Moreover,the COMSOL Multiphysics simulation was conducted to reveal the effects on homogeneous Li ions distribution derived from the above-mentioned OPAN/CMOF framework and electrical insulation/conduction design.These electrochemical and simulated results shed light on the difficulties of designing stable and safe Li metal anode via optimizing the 3D frameworks.展开更多
A series of Yb：Tm：LiNbO_3 crystals doped with x mol% Hf^（4＋）ions（x = 2, 4, and 6） were grown by the Czochralski method. The dopant occupancy and defect structure of Hf：Yb：Tm：LiNbO_3 crystals were investigate...A series of Yb：Tm：LiNbO_3 crystals doped with x mol% Hf^（4＋）ions（x = 2, 4, and 6） were grown by the Czochralski method. The dopant occupancy and defect structure of Hf：Yb：Tm：LiNbO_3 crystals were investigated by x-ray diffraction and infrared transmission spectra. The influence of Hf^（4＋）ions concentration on UV–VIS–NIR absorption spectra of Hf：Yb：Tm：LiNbO_3 crystals was discussed. The upconversion luminescence of Hf：Yb：Tm：LiNbO_3 crystals was obtained under 980 nm excitation. Strong emissions were observed at 475 nm in the blue wavelength range and 651 nm in the red wavelength range. Remarkably, enhancement of the red and blue upconversion luminescence was achieved by tridoping Hf^（4＋）ions.展开更多
基金financially supported by the National Key Research and Development Program of China(2022YFA1505700,2019YFA0210403)the National Natural Science Foundation of China(52102216)+4 种基金the Natural Science Foundation of Fujian Province(2022J01625,2022-S-002)the Anhui Key Laboratory of Nanomaterials and Nanotechnology,the Major Science and Technology Projects in Anhui Province(202305a12020006)the Open Project of State Key Laboratory of Inorganic Synthesis and Preparative Chemistry(2025-22)the Innovation Training Program for College Students(cxxl-2024131,cxxl-2024136)support by Transmission Electron Microscope Platform and High-performance Computing Platform of Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China。
文摘Layered V_(2)O_(5) cathode holds the merits of high theoretical specific capacity(589 mA h g^(-1))in aqueous zinc-ion batteries(AZIBs),yet it still suffers from inferior bulk conductivity and structure degradation notably during prolonged cycling.Herein,we ingeniously design cations(Na^(+)/Co^(2+)/Al^(3+))and anion(F^(-))synergistic-doped hydrated V_(2)O_(5)·0.48H_(2)O cathode(VNACOF)to enhance the electronic and spatial effects in the bulk.A range of in-situ,ex-situ characterizations,and DFT calculations profoundly clarify the strengthened ionic/electronic conductivities,structural stability,and Zn^(2+)diffusion kinetics.As a result,the VNACOF displays a superior discharge capacity(529 mA h g^(-1)@0.1 C),rate capabilities(488 mA h g^(-1)@0.5 C,437 mA h g^(-1)@1C),and cycling stability(301 mA h g^(-1)@10 C@5000 cycles@93%)with sufficient energy density(393 W h kg^(-1)),Furthermore,the pouch-cells with high-load(60 mg)also deliver superior cyclic(2 C@178 mA h g^(-1)@1000 cycles@90%)and rate performance(132 mA h g^(-1)@5 C),revealing great application potential for high-energy-density and high-stability AZIBs.
基金supported by the National Natural Science Foundation of China(52372164,52302085,and 52172174)the Anhui Provincial Natural Science Foundation(2308085Y05 and 2308085QE143)+1 种基金the Key Natural Science Research Project of Anhui Provincial Education Department(2023AH050094)the startup grants from Anhui University(S020318031/001).
文摘Aqueous Zn ion batteries(ZIBs)have received extensive attention due to their intrinsic safety,high abundance,and low cost.However,uncontrolled dendrite growth and water-induced side reactions at electrod e/electrolyte interfaces hinder the advancement of ZIBs.Herein,density functional theory(DFT)calculation indicates that Zn heptafluorobutyrate can facilitate uniform Zn^(2+)deposition by leveraging the abundant zincophilic groups(e.g.,-COO^(-)and-CF)and inhibit water-induced side reactions due to the presence of hydrophobic carbon chains.A Zn heptafluorobutyrate protective layer(denoted as ZFA)is constructed on the metallic Zn surface in situ by acid etching process to control Zn^(2+)desolvation and nucleation behaviors,ensuring enhanced reversibility and stability of Zn anodes.Consequently,the Zn@ZFA anode demonstrates stable operation for more than 2200 h at 1 mA cm^(-2)and over 7300cycles at 40 mA cm^(-2),with high Coulombic efficiency of 99.8%over 1900 cycles at 5 mA cm^(-2).Impressively,Zn@ZFA‖VO_(2)full cell achieves exceptional cycle life(204 mA h g^(-1)after 750 cycles at 3 A g^(-1))and remarkable rate performance(236 mA g^(-1)at 10 A g^(-1)).This work provides an insightful guidance for constructing a protection layer of dendrite-free Zn anodes for high-performance ZIBs.
基金supported by the National Natural Science Foundation of China (52302292, 52302058, 52302085)the China Postdoctoral Science Foundation (2021M702225)+1 种基金the Anhui Province University Natural Science Research Project (2023AH030093, 2023AH040301)the Startup Research Fund of Chaohu University (KYQD-2023005, KYQD-2023051)。
文摘Composite Li metal anodes based on three-dimensional(3D) porous frameworks have been considered as an effective material for achieving stable Li metal batteries with high energy density.However,uneven Li deposition behavior still occurs at the top of 3D frameworks owing to the local accumulation of Li ions.To promote uniform Li deposition without top dendrite growth,herein,a layered multifunctional framework based on oxidation-treated polyacrylonitrile(OPAN) and metal-organic framework(MOF) derivatives was proposed for rationally regulating the distribution of Li ions flux,nucleation sites,and electrical conductivity.Profiting from these merits,the OPAN/carbon nano fiber-MOF(CMOF) composite framework demonstrated a reversible Li plating/stripping behavior for 500 cycles with a stable Coulombic efficiency of around 99.0% at the current density of 2 mA/cm~2.Besides,such a Li composite anode exhibited a superior cycle lifespan of over 1300 h under a low polarized voltage of 18 mV in symmetrical cells.When the Li composite anode was paired with LiFePO_(4)(LFP) cathode,the obtained full cell exhibited a stable cycling over 500 cycles.Moreover,the COMSOL Multiphysics simulation was conducted to reveal the effects on homogeneous Li ions distribution derived from the above-mentioned OPAN/CMOF framework and electrical insulation/conduction design.These electrochemical and simulated results shed light on the difficulties of designing stable and safe Li metal anode via optimizing the 3D frameworks.
基金Project supported by Special Funds of Harbin Innovation Talents in Science and Technology Research,China(Grant No.2015RQQXJ045)Science Funds for the Young Innovative Talents of HUST,China
文摘A series of Yb：Tm：LiNbO_3 crystals doped with x mol% Hf^（4＋）ions（x = 2, 4, and 6） were grown by the Czochralski method. The dopant occupancy and defect structure of Hf：Yb：Tm：LiNbO_3 crystals were investigated by x-ray diffraction and infrared transmission spectra. The influence of Hf^（4＋）ions concentration on UV–VIS–NIR absorption spectra of Hf：Yb：Tm：LiNbO_3 crystals was discussed. The upconversion luminescence of Hf：Yb：Tm：LiNbO_3 crystals was obtained under 980 nm excitation. Strong emissions were observed at 475 nm in the blue wavelength range and 651 nm in the red wavelength range. Remarkably, enhancement of the red and blue upconversion luminescence was achieved by tridoping Hf^（4＋）ions.
