We have prepared a high-density polyaniline(PANI) paste(50 mg/m L), with similar physical properties to those of paints or pigments. The synthesis of PANI is confirmed by Fourier transform infrared(FT-IR) spectr...We have prepared a high-density polyaniline(PANI) paste(50 mg/m L), with similar physical properties to those of paints or pigments. The synthesis of PANI is confirmed by Fourier transform infrared(FT-IR) spectroscopy. The morphologies of PANI, doped PANI, and doped PANI paste are confirmed by scanning electron microscopy(SEM). Particles of doped PANI paste are approximately 40–50 nm in diameter, with a uniform and cubic shape. The electrochemical performances of doped PANI paste using both liquid and solid polymer electrolytes have been measured by galvanostatic charge and discharge process. The cell fabricated with doped PANI paste and the solid polymer electrolyte exhibits a discharge capacity of ~87 μAh/cm2(64.0 m Ah/g) at the second cycle and~67 μAh/cm2(50.1 m Ah/g) at the 100 th cycle.展开更多
The results of the photoelectron spectra for the oxysulfide glasses in the Li2S-B2O3 (-LiBr) spotems are discussed. The peak resolved S2p spectra show the existences of bridging and non-bridging S. The values of the b...The results of the photoelectron spectra for the oxysulfide glasses in the Li2S-B2O3 (-LiBr) spotems are discussed. The peak resolved S2p spectra show the existences of bridging and non-bridging S. The values of the binding energy of Lits indicate the chemical environmemts of Li+ ions.展开更多
Herein, we developed novel silicon-carbon-nitrogen (SiCN) composites synthesized by pyrolyzing silsesquiazane polymer as an anode material for rechargeable lithium-ion batteries. Among variable pyrolysis temperature...Herein, we developed novel silicon-carbon-nitrogen (SiCN) composites synthesized by pyrolyzing silsesquiazane polymer as an anode material for rechargeable lithium-ion batteries. Among variable pyrolysis temperatures of 700 ℃, 1000 ℃ and 1300 ℃, the SiCN composites prepared at 1000 ℃ showed the highest capacity with outstanding battery cycle life by cyclic voltammetry and electrochemical impedance spectroscopy. Such good battery and electrochemical performances should be attributed to a proper ratio of carbon and nitrogen or oxygen in the SiCN composites. Furthermore, our SiCN electrode possessed better lithium ion conductivity than pure silicon nanoparticles. This work demonstrates that polymer-derived composites are among the promising strategies to achieve highly stable silicon anodes for rechargeable batteries.展开更多
Ion conduction plays key roles in electrochemical systems,including fuel cells,lithium ion batteries,and metal-air batteries.Covalent organic frameworks(COFs),as a new class of porous polymers,constructed by pre-desig...Ion conduction plays key roles in electrochemical systems,including fuel cells,lithium ion batteries,and metal-air batteries.Covalent organic frameworks(COFs),as a new class of porous polymers,constructed by pre-designable building blocks,are ideal hosts to accommodate ionic carries for conduction because of their straightforward pore channels,tunable pore size,controllable pore environment,and good chemical and thermal stability.Different from proton conduction,how to achieve high lithium ion conduction is still a challenge as it is difficult to dissociate ionic bonds of the lithium salts.To facilitate the dissociation of lithium salts,COFs with different pores and skeletons are well designed and constructed.This review focuses on emerging developments of lithium ion conduction in COFs,and discusses the structures of these COFs and conductive performance to elucidate the structure-property correlations.Furthermore,we have concluded the remaining challenge and future direction in these COF-based lithium conductive areas.This review provides deeper insight into COFs for ionic conduction.展开更多
基金supported by a grant from the Fundamental R&D Program for Core Technology of Materials funded by the Korean Ministry of Knowledge Economy and by the Priority Research Centers Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education,Science and Technology(2009-0093818)
文摘We have prepared a high-density polyaniline(PANI) paste(50 mg/m L), with similar physical properties to those of paints or pigments. The synthesis of PANI is confirmed by Fourier transform infrared(FT-IR) spectroscopy. The morphologies of PANI, doped PANI, and doped PANI paste are confirmed by scanning electron microscopy(SEM). Particles of doped PANI paste are approximately 40–50 nm in diameter, with a uniform and cubic shape. The electrochemical performances of doped PANI paste using both liquid and solid polymer electrolytes have been measured by galvanostatic charge and discharge process. The cell fabricated with doped PANI paste and the solid polymer electrolyte exhibits a discharge capacity of ~87 μAh/cm2(64.0 m Ah/g) at the second cycle and~67 μAh/cm2(50.1 m Ah/g) at the 100 th cycle.
文摘The results of the photoelectron spectra for the oxysulfide glasses in the Li2S-B2O3 (-LiBr) spotems are discussed. The peak resolved S2p spectra show the existences of bridging and non-bridging S. The values of the binding energy of Lits indicate the chemical environmemts of Li+ ions.
基金supported by the Human Resources Development of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) grant funded by the Ministry of Knowledge Economy (No. 20124030200070), Republic of Korea
文摘Herein, we developed novel silicon-carbon-nitrogen (SiCN) composites synthesized by pyrolyzing silsesquiazane polymer as an anode material for rechargeable lithium-ion batteries. Among variable pyrolysis temperatures of 700 ℃, 1000 ℃ and 1300 ℃, the SiCN composites prepared at 1000 ℃ showed the highest capacity with outstanding battery cycle life by cyclic voltammetry and electrochemical impedance spectroscopy. Such good battery and electrochemical performances should be attributed to a proper ratio of carbon and nitrogen or oxygen in the SiCN composites. Furthermore, our SiCN electrode possessed better lithium ion conductivity than pure silicon nanoparticles. This work demonstrates that polymer-derived composites are among the promising strategies to achieve highly stable silicon anodes for rechargeable batteries.
基金financial support from the Natural Science Foundation of Shanghai(20ZR1464000)supports from the National Natural Science Foundation of China(21878322,22075309)the Science and Technology Commission of Shanghai Municipality(19ZR1479200,22ZR1470100)。
文摘Ion conduction plays key roles in electrochemical systems,including fuel cells,lithium ion batteries,and metal-air batteries.Covalent organic frameworks(COFs),as a new class of porous polymers,constructed by pre-designable building blocks,are ideal hosts to accommodate ionic carries for conduction because of their straightforward pore channels,tunable pore size,controllable pore environment,and good chemical and thermal stability.Different from proton conduction,how to achieve high lithium ion conduction is still a challenge as it is difficult to dissociate ionic bonds of the lithium salts.To facilitate the dissociation of lithium salts,COFs with different pores and skeletons are well designed and constructed.This review focuses on emerging developments of lithium ion conduction in COFs,and discusses the structures of these COFs and conductive performance to elucidate the structure-property correlations.Furthermore,we have concluded the remaining challenge and future direction in these COF-based lithium conductive areas.This review provides deeper insight into COFs for ionic conduction.