A novel inorganic-organic composite membrane based on sulfonated polyether ether ketone(SPEEK) with embedded phosphotungstic acid(PWA) for direct methanol fuel cells(DMFC) was prepared. IR spectra results indicate tha...A novel inorganic-organic composite membrane based on sulfonated polyether ether ketone(SPEEK) with embedded phosphotungstic acid(PWA) for direct methanol fuel cells(DMFC) was prepared. IR spectra results indicate that PWA was kept in SPEEK matrix as the Keggin structure. From SEM micrograph, it could be found that the solid PWA were well mixed with SPEEK matrix and showed no agglomeration in the membrane. Proton conductivity of the PWA/SPEEK composite membrane is higher than that of pure SPEEK membrane, and is similar or superior to that of Nafion ○R 115 membrane in the temperature range 80—110 ℃. Methanol permeability of the PWA/SPEEK membrane was considerably smaller than that of Nafion ○R 115 membrane. Because of its high conductivity and low methanol permeability, the PWA/SPEEK membrane seems to be an excellent candidate for DMFC applications.展开更多
A series of Cr^(3+)-substituted Na_(1+x)Ti_(2−x)Cr_(x)P_(3)O_(12)(x=0.1,0.2,0.3,0.4,0.5,molar fraction)solid electrolytes were prepared by the solid-phase reaction method.The effects of Cr^(3+)ions on the phase compos...A series of Cr^(3+)-substituted Na_(1+x)Ti_(2−x)Cr_(x)P_(3)O_(12)(x=0.1,0.2,0.3,0.4,0.5,molar fraction)solid electrolytes were prepared by the solid-phase reaction method.The effects of Cr^(3+)ions on the phase composition,microstructure,and electrochemical ion conductivity of Na-based conductors were studied using X-ray powder diffraction,field emission scanning electron microscopy,and AC impedance measurement.The results show that the main crystal phase of NaTi_(2)(PO_(4))_(3) is formed in the solid electrolytes.The substitution of Ti4+sites by 15 at.%Cr^(3+)ions contributes to the enhancement of electrical conductivity,which is attributed to the combined effect of suppressing the formation of impurity phases,broadening ion channels,and improving the bonding degree of grains.Na_(1.3)Ti_(1.7)Cr_(0.3)P_(3)O_(12) electrolyte can obtain the best ionic conductivity of 6.13×10^(−6)S/cm at room temperature,which is 8 times that of the undoped NaTi_(2)(PO_(4))_(3) electrolyte.展开更多
In the current aera of rapid development in the field of electric vehicles and electrochemical energy storage,solid-state battery technology is attracting much research and attention.Solid-state electrolytes,as the ke...In the current aera of rapid development in the field of electric vehicles and electrochemical energy storage,solid-state battery technology is attracting much research and attention.Solid-state electrolytes,as the key component of next-generation battery technology,are favored for their high safety,high energy density,and long life.However,finding high-performance solid-state electrolytes is the primary challenge for solid-state battery applications.Focusing on inorganic solid-state electrolytes,this work highlights the need for ideal solid-state electrolytes to have low electronic conductivity,good thermal stability,and structural and phase stability.Traditional experimental and theoretical computational methods suffer from inefficiency,thus machine learning methods become a novel path to intelligently predict material properties by analyzing a large number of inorganic structural properties and characteristics.Through the gradient descent-based XGBoost algorithm,we successfully predicted the energy band structure and stability of the materials,and screened out only 194 ideal solid-state electrolyte structures from more than 6000 structures that satisfy the requirements of low electronic conductivity and stability simultaneously,which greatly accelerated the development of solid-state batteries.展开更多
文摘A novel inorganic-organic composite membrane based on sulfonated polyether ether ketone(SPEEK) with embedded phosphotungstic acid(PWA) for direct methanol fuel cells(DMFC) was prepared. IR spectra results indicate that PWA was kept in SPEEK matrix as the Keggin structure. From SEM micrograph, it could be found that the solid PWA were well mixed with SPEEK matrix and showed no agglomeration in the membrane. Proton conductivity of the PWA/SPEEK composite membrane is higher than that of pure SPEEK membrane, and is similar or superior to that of Nafion ○R 115 membrane in the temperature range 80—110 ℃. Methanol permeability of the PWA/SPEEK membrane was considerably smaller than that of Nafion ○R 115 membrane. Because of its high conductivity and low methanol permeability, the PWA/SPEEK membrane seems to be an excellent candidate for DMFC applications.
基金supported by the National Natural Science Foundation of China(No.51972344)the Natural Science Foundation of Hunan Province,China(No.2018JJ3646).
文摘A series of Cr^(3+)-substituted Na_(1+x)Ti_(2−x)Cr_(x)P_(3)O_(12)(x=0.1,0.2,0.3,0.4,0.5,molar fraction)solid electrolytes were prepared by the solid-phase reaction method.The effects of Cr^(3+)ions on the phase composition,microstructure,and electrochemical ion conductivity of Na-based conductors were studied using X-ray powder diffraction,field emission scanning electron microscopy,and AC impedance measurement.The results show that the main crystal phase of NaTi_(2)(PO_(4))_(3) is formed in the solid electrolytes.The substitution of Ti4+sites by 15 at.%Cr^(3+)ions contributes to the enhancement of electrical conductivity,which is attributed to the combined effect of suppressing the formation of impurity phases,broadening ion channels,and improving the bonding degree of grains.Na_(1.3)Ti_(1.7)Cr_(0.3)P_(3)O_(12) electrolyte can obtain the best ionic conductivity of 6.13×10^(−6)S/cm at room temperature,which is 8 times that of the undoped NaTi_(2)(PO_(4))_(3) electrolyte.
基金supported by the National Natural Science Foundation of China(No.21421063,No.21473166,No.21573211,No.21633007,No.21790350,No.21803067,No.91950207)the Chinese Academy of Sciences(QYZDB-SSW-SLH018)+3 种基金the Anhui Initiative in Quantum Information Technologies(AHY090200)the USTC-NSRL Joint Funds(UN2018LHJJ)the Anhui Provincial Natural Science Foundation(2108085QB63)Numerical Theoretical simulations were done in the Supercomputing Center of USTC.
文摘In the current aera of rapid development in the field of electric vehicles and electrochemical energy storage,solid-state battery technology is attracting much research and attention.Solid-state electrolytes,as the key component of next-generation battery technology,are favored for their high safety,high energy density,and long life.However,finding high-performance solid-state electrolytes is the primary challenge for solid-state battery applications.Focusing on inorganic solid-state electrolytes,this work highlights the need for ideal solid-state electrolytes to have low electronic conductivity,good thermal stability,and structural and phase stability.Traditional experimental and theoretical computational methods suffer from inefficiency,thus machine learning methods become a novel path to intelligently predict material properties by analyzing a large number of inorganic structural properties and characteristics.Through the gradient descent-based XGBoost algorithm,we successfully predicted the energy band structure and stability of the materials,and screened out only 194 ideal solid-state electrolyte structures from more than 6000 structures that satisfy the requirements of low electronic conductivity and stability simultaneously,which greatly accelerated the development of solid-state batteries.
