Halide solid-state electrolytes(SSEs)with high ionic conductivity and excellent compatibility with highvoltage oxide cathodes in all-solid-state lithium batteries(ASSLBs)offer improved safety and cycling performance.H...Halide solid-state electrolytes(SSEs)with high ionic conductivity and excellent compatibility with highvoltage oxide cathodes in all-solid-state lithium batteries(ASSLBs)offer improved safety and cycling performance.However,the ionic conductivity of halide SSEs at room temperature(RT)and their stability against lithium(Li)metal anodes still require further enhancement.In this study,Li_(2+x)ZrCl_(6-x)S_(x)(0≤x≤1)SSEs,featuring two highly amorphous phases,are synthesized via an aliovalent sulfursubstitution strategy.Notably,a new phase(C2/m),distinct from Li_(2)ZrCl_(6)(LZC)(p3m1),is induced by modulating the sulfur substitution level for chlorine.Consequently,the crystallinity of the coexisting two-phase SSEs is significantly lower than that of the single-phase material.Owing to their highly amorphous nature,the ionic conductivity of Li_(2.25)ZrCl_(5.75)S_(0.25)(LZCS0.25)increases from 0.33 mS cm^(-1)(LZC)to0.97 mS cm^(-1)at RT.In addition,LZCS0.25 exhibits higher compressibility and lower reduction potential(1.78 V vs.2.34 V for LZC),and the Li/LZCS0.25/Li symmetric cell exhibits improved cycling stability.ASSLBs employing LZCS0.25 and LiCoO_(2) or single-crystal LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2) demonstrate high reversible specific capacity and excellent long-term cycling stability.This strategy for regulating the amorphous structure provides valuable guidance for the development of high-performance SSEs for ASSLBs.展开更多
Dielectric capacitors,as physical powers,are critical components of advanced electronics and pulse power systems.However,achieving high energy efficiency without sacrificing recoverable energy density remains a challe...Dielectric capacitors,as physical powers,are critical components of advanced electronics and pulse power systems.However,achieving high energy efficiency without sacrificing recoverable energy density remains a challenge for most dielectric materials.In this work,the aliovalent Sm^(3+)doped Ba_(0.12)Na_(0.3)Bi_(0.3)Sr_(0.28)TiO_(3)(BNBST)relaxor ferroelectric at the A site was used to design a defect-induced phase/domain structure to improve polarization switching.A high energy efficiency of 91%,together with a recoverable energy density of 2.1 J/cm^(3),was achieved in Sm_(0.07)–BNBST ceramics at a low electric field of 114 kV/cm,exceeding those of other dielectric materials under the same electric field.In addition,Sm_(0.07)–BNBST ceramics exhibit good energy storage stability and endurance and fast charging‒discharging speeds,demonstrating their great potential in electrostatic capacitor applications.This work provides an approach to achieve highperformance dielectrics through aliovalent rare earth doping and builds a close relationship between the defect-engineered phase/domain structure and polarization switching for energy storage.展开更多
Ferroelectric barium strontium titanate （BST） glass-ceramics doped with different content of La2O3 were prepared via the melt-quenching technique followed by controlled crystallization. The microstructures of crysta...Ferroelectric barium strontium titanate （BST） glass-ceramics doped with different content of La2O3 were prepared via the melt-quenching technique followed by controlled crystallization. The microstructures of crystallized samples were examined by X-ray diffraction and scanning electron microscopy. Dielectric properties were also investigated. The aliovalent substitution of Ba by La induced dispersion of semiconducting BaxSr1-xTi03 crystallites sealed in a glassy silicate matrix, which increased the εr and loss tangent values of the BST glass- ceramic. The experimental results indicate that aliovalent substitution is an effective method to process glass-ceramics with better dielectric properties.展开更多
Strategy of Sb-substitution is carried out on the template structure Na4Sn0.67M0.33S4(M=Si,Ge),which affords a series of quinary sulfide-based sodium fast ionic conductors formulated as Na4-x[Sn0.67M0.33]1-xSbxS4(M=Si...Strategy of Sb-substitution is carried out on the template structure Na4Sn0.67M0.33S4(M=Si,Ge),which affords a series of quinary sulfide-based sodium fast ionic conductors formulated as Na4-x[Sn0.67M0.33]1-xSbxS4(M=Si,x=0.1,0.2,0.3;M=Ge,x=0.2.).Among them,the highest ambient ionic conductivity(1.75×10^-4 S cm^-1)is achieved when M=Si and x=0.2.The new fast ionic conductor Na3.8[Sn0.67Si0.33]0.8Sb0.2S4 is isostructural to its structure template Na4Sn0.67Si0.33S4 and thus crystallizes in the space group of I41/acd.It is shown that the incorporation of Sb improves the ionic conductivity.The study of lattice parameters shows that the improvement of the ion conductivity by Sbsubstitution is mainly due to the enlarged crystal lattice.Furthermore,using Na3.8[Sn0.67Si0.33]0.8Sb0.2S4as solid electrolytes,room temperature all-solid-state sodium battery of Se0.05S0.95@pPAN/Na3Sn is realized,which proves the novel fast ionic conductor a potential candidate to apply in sodium solid state battery.This work not only extends the scope of Na4[Sn0.67Si0.33]S4,the I41/acd space group template,but also deepens the understanding of the lattice size effect on the structure and property relationship by aliovalent substitution.展开更多
All-solid-state batteries(ASSBs) with inorganic solid-state-electrolytes(SSEs) have been regarded as the promising candidate for next-generation energy storage due to their high energy density and outstanding safety p...All-solid-state batteries(ASSBs) with inorganic solid-state-electrolytes(SSEs) have been regarded as the promising candidate for next-generation energy storage due to their high energy density and outstanding safety performance.However,the representative oxide and sulfide electrolytes suffer from low ionic conductivity and poor(electro)chemical stability,respectively.Herein,we report a series of new halide superionic conductors Li_(2+x)Hf_(1-x)In_(x)Cl_(6) with high ionic conductivity up to 1.05 mS cm^(-1) at 30 ℃ that are simultaneously stable to high voltage.By means of the characterization techniques and bond-valence site energy(BVSE) calculation,insights into the effect of the phase transformation and underlying ionic transport mechanism by In substitution for Hf in Li_(2)HfCl_(6) are provided.Importantly,with the increased amount of aliovalent substitution in Li_(2+x)Hf_(1-x)In_(x)Cl_(6) microcrystal framework,a gradual structure evolution from trigonal to monoclinic phase has been observed,which is accompanied by the redistribution of Li-ions to generate two dimensionally(2D) preferable diffusion pathways through octahedral-tetrahe dral-octahedral sites in In^(3+)-substituted Li_(2)HfCl_(6).Additionally,due to the oxidative stability of Insubstituted Li_(2)HfCl_(6),the bulk-type ASSBs with bare LiCoO_(2) deliver distinguished electrochemical performance.展开更多
文摘Halide solid-state electrolytes(SSEs)with high ionic conductivity and excellent compatibility with highvoltage oxide cathodes in all-solid-state lithium batteries(ASSLBs)offer improved safety and cycling performance.However,the ionic conductivity of halide SSEs at room temperature(RT)and their stability against lithium(Li)metal anodes still require further enhancement.In this study,Li_(2+x)ZrCl_(6-x)S_(x)(0≤x≤1)SSEs,featuring two highly amorphous phases,are synthesized via an aliovalent sulfursubstitution strategy.Notably,a new phase(C2/m),distinct from Li_(2)ZrCl_(6)(LZC)(p3m1),is induced by modulating the sulfur substitution level for chlorine.Consequently,the crystallinity of the coexisting two-phase SSEs is significantly lower than that of the single-phase material.Owing to their highly amorphous nature,the ionic conductivity of Li_(2.25)ZrCl_(5.75)S_(0.25)(LZCS0.25)increases from 0.33 mS cm^(-1)(LZC)to0.97 mS cm^(-1)at RT.In addition,LZCS0.25 exhibits higher compressibility and lower reduction potential(1.78 V vs.2.34 V for LZC),and the Li/LZCS0.25/Li symmetric cell exhibits improved cycling stability.ASSLBs employing LZCS0.25 and LiCoO_(2) or single-crystal LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2) demonstrate high reversible specific capacity and excellent long-term cycling stability.This strategy for regulating the amorphous structure provides valuable guidance for the development of high-performance SSEs for ASSLBs.
基金supported by the National Natural Science Foundation of China(No.52267002)the Natural Science Foundation of Jiangxi Province(No.20212ACB204010)the Science&Technology Research Project of Jiangxi Provincial Education Department(No.GJJ211301).
文摘Dielectric capacitors,as physical powers,are critical components of advanced electronics and pulse power systems.However,achieving high energy efficiency without sacrificing recoverable energy density remains a challenge for most dielectric materials.In this work,the aliovalent Sm^(3+)doped Ba_(0.12)Na_(0.3)Bi_(0.3)Sr_(0.28)TiO_(3)(BNBST)relaxor ferroelectric at the A site was used to design a defect-induced phase/domain structure to improve polarization switching.A high energy efficiency of 91%,together with a recoverable energy density of 2.1 J/cm^(3),was achieved in Sm_(0.07)–BNBST ceramics at a low electric field of 114 kV/cm,exceeding those of other dielectric materials under the same electric field.In addition,Sm_(0.07)–BNBST ceramics exhibit good energy storage stability and endurance and fast charging‒discharging speeds,demonstrating their great potential in electrostatic capacitor applications.This work provides an approach to achieve highperformance dielectrics through aliovalent rare earth doping and builds a close relationship between the defect-engineered phase/domain structure and polarization switching for energy storage.
基金Financial supports from the National Natural Science Foundation of China (No. 50902082)the State Key Laboratory of Electrical Insulation and Power Equipment (EIPE11208) are gratefully acknowledged
文摘Ferroelectric barium strontium titanate （BST） glass-ceramics doped with different content of La2O3 were prepared via the melt-quenching technique followed by controlled crystallization. The microstructures of crystallized samples were examined by X-ray diffraction and scanning electron microscopy. Dielectric properties were also investigated. The aliovalent substitution of Ba by La induced dispersion of semiconducting BaxSr1-xTi03 crystallites sealed in a glassy silicate matrix, which increased the εr and loss tangent values of the BST glass- ceramic. The experimental results indicate that aliovalent substitution is an effective method to process glass-ceramics with better dielectric properties.
基金supported by the National Natural Science Foundation of China(21975087 and 51902116)。
文摘Strategy of Sb-substitution is carried out on the template structure Na4Sn0.67M0.33S4(M=Si,Ge),which affords a series of quinary sulfide-based sodium fast ionic conductors formulated as Na4-x[Sn0.67M0.33]1-xSbxS4(M=Si,x=0.1,0.2,0.3;M=Ge,x=0.2.).Among them,the highest ambient ionic conductivity(1.75×10^-4 S cm^-1)is achieved when M=Si and x=0.2.The new fast ionic conductor Na3.8[Sn0.67Si0.33]0.8Sb0.2S4 is isostructural to its structure template Na4Sn0.67Si0.33S4 and thus crystallizes in the space group of I41/acd.It is shown that the incorporation of Sb improves the ionic conductivity.The study of lattice parameters shows that the improvement of the ion conductivity by Sbsubstitution is mainly due to the enlarged crystal lattice.Furthermore,using Na3.8[Sn0.67Si0.33]0.8Sb0.2S4as solid electrolytes,room temperature all-solid-state sodium battery of Se0.05S0.95@pPAN/Na3Sn is realized,which proves the novel fast ionic conductor a potential candidate to apply in sodium solid state battery.This work not only extends the scope of Na4[Sn0.67Si0.33]S4,the I41/acd space group template,but also deepens the understanding of the lattice size effect on the structure and property relationship by aliovalent substitution.
基金the financial support of 21C Innovation Laboratory, Contemporary Amperex Technology Ltd. (21COP-202212)the Foundation of Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), the Nankai University, Foundation of State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering (2022-K15)+1 种基金the China University of Mining & Technology (Beijing), the Foundation of Top-notch Innovative Talents Cultivation (BBJ2023031) of China University of Mining & Technology (Beijing)the National Natural Science Foundation of China (51672029 and 51372271)。
文摘All-solid-state batteries(ASSBs) with inorganic solid-state-electrolytes(SSEs) have been regarded as the promising candidate for next-generation energy storage due to their high energy density and outstanding safety performance.However,the representative oxide and sulfide electrolytes suffer from low ionic conductivity and poor(electro)chemical stability,respectively.Herein,we report a series of new halide superionic conductors Li_(2+x)Hf_(1-x)In_(x)Cl_(6) with high ionic conductivity up to 1.05 mS cm^(-1) at 30 ℃ that are simultaneously stable to high voltage.By means of the characterization techniques and bond-valence site energy(BVSE) calculation,insights into the effect of the phase transformation and underlying ionic transport mechanism by In substitution for Hf in Li_(2)HfCl_(6) are provided.Importantly,with the increased amount of aliovalent substitution in Li_(2+x)Hf_(1-x)In_(x)Cl_(6) microcrystal framework,a gradual structure evolution from trigonal to monoclinic phase has been observed,which is accompanied by the redistribution of Li-ions to generate two dimensionally(2D) preferable diffusion pathways through octahedral-tetrahe dral-octahedral sites in In^(3+)-substituted Li_(2)HfCl_(6).Additionally,due to the oxidative stability of Insubstituted Li_(2)HfCl_(6),the bulk-type ASSBs with bare LiCoO_(2) deliver distinguished electrochemical performance.
