Hollow-structured Cu_(0.3)Co_(2.7)O_(4) microspheres have been synthesized by a simple one-pot template-free hydrothermal method with copper sulfate,cobalt acetate and ammonia as raw materials.The products were charac...Hollow-structured Cu_(0.3)Co_(2.7)O_(4) microspheres have been synthesized by a simple one-pot template-free hydrothermal method with copper sulfate,cobalt acetate and ammonia as raw materials.The products were characterized by powder X-ray diffraction,energy dispersive X-ray analysis,selected area electron diffraction,high-resolution transmission electron microscopy,scanning electron microscopy and BET measurements.The research results show that the hollow Cu_(0.3)Co_(2.7)O_(4) microspheres consist of single-crystalline nanocubes with the diameter of about 20 nm.The formation mechanism of hollow Cu_(0.3)Co_(2.7)O_(4) microspheres is suggested as Ostwald ripening in a solid-solution-solid process,and Cu_(0.3)Co_(2.7)O_(4) microspheres are mesoporous containing two pore sizes of 3.3 and 5.9 nm.The as-prepared Cu_(0.3)Co_(2.7)O_(4) sensors have optimal gas responses to 50×10^(−6) mg/m^(3) C_(2)H_(5)OH at 190℃.展开更多
Co3 O4 is one of the most studied transition-metal oxides for use in energy-storage devices.However,its poor conductivity and stability limit its application.In this study,a facile method for anchoring Co3 O4-encapsul...Co3 O4 is one of the most studied transition-metal oxides for use in energy-storage devices.However,its poor conductivity and stability limit its application.In this study,a facile method for anchoring Co3 O4-encapsulated Cu2 O nanocubes on porous carbon(PC) to form Cu2 O@Co3 O4/PC was developed.The Cu2 O@Co3 O4/PC composite exhibited superior electrochemical performance as a supercapacitor electrode material.The resultant supercapacitor delivered high specific capacitance(1096 F g^-1 at 1 A g^-1),high rate capability(83 % retention at 10 A g^-1),and excellent cycling stability(95 % retention of initial capacitance after 3000 cycles).Moreover,an asymmetric supercapacitor fabricated by coupling a Cu2 O@Co3 O4/PC positive electrode with a reduced graphene oxide negative electrode exhibited high energy density(32.1 W h kg^-1 at 700 W kg^-1).Thus,our results demonstrate that Cu2 O@Co3 O4/PC is a promising electrode material for energy-storage devices.展开更多
LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)is considered as a promising cathode for high-energy-density solid-sate Li metal battery for its high theoretical capacity.However,the high oxidizability and structural instabili...LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)is considered as a promising cathode for high-energy-density solid-sate Li metal battery for its high theoretical capacity.However,the high oxidizability and structural instability during charge limit its practical applications.In this work,1%(in mass)of nanosized Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP)was coated on NCM811 to enhance its electrochemical stability with a ceramic/polymer com-posite electrolyte.A robust,ultrathin(11 mm)composite electrolyte film was prepared by combining poly(vinylidene fluoride)(PVDF)with polyethylene oxide(PEO)-Li_(6.5)La_(3)Zr_(1.5)Ta_(0.5)O_(12)(LLZTO).An in-situ polymerization process was used to enhance the interface between the PVDF/PEO-LLZTO(PPL)com-posite electrolyte and the LATP-coated NCM811(LATP-NCM811).Coin-type Li|LATP-NCM811 cell with the PPL electrolyte exhibits stable cycling with an 81%capacity retention after 100 cycles at 0.5 C.Pouch-type cell was also fabricated,which can be stably cycled for 70 cycles at 0.5 C/1.0 C(80%retention),and withstand abuse tests of bending,cutting and nail penetration.This work provides an applicable method to fabricate solid-state Li metal batteries with high performance.展开更多
基金Project(51202066)supported by the National Natural Science Foundation of ChinaProject(NCET-13-0784)supported by the Program for New Century Excellent Talents in University of China。
文摘Hollow-structured Cu_(0.3)Co_(2.7)O_(4) microspheres have been synthesized by a simple one-pot template-free hydrothermal method with copper sulfate,cobalt acetate and ammonia as raw materials.The products were characterized by powder X-ray diffraction,energy dispersive X-ray analysis,selected area electron diffraction,high-resolution transmission electron microscopy,scanning electron microscopy and BET measurements.The research results show that the hollow Cu_(0.3)Co_(2.7)O_(4) microspheres consist of single-crystalline nanocubes with the diameter of about 20 nm.The formation mechanism of hollow Cu_(0.3)Co_(2.7)O_(4) microspheres is suggested as Ostwald ripening in a solid-solution-solid process,and Cu_(0.3)Co_(2.7)O_(4) microspheres are mesoporous containing two pore sizes of 3.3 and 5.9 nm.The as-prepared Cu_(0.3)Co_(2.7)O_(4) sensors have optimal gas responses to 50×10^(−6) mg/m^(3) C_(2)H_(5)OH at 190℃.
基金This work was supported by the National Natural Science Foundation of China(Nos.51861005 and 51861004)the Innovation Project of Guangxi Graduate Education(No.YCSW2019149)the Guangxi Natural Science Foundation(No.2017GXNSFDA198018)。
文摘Co3 O4 is one of the most studied transition-metal oxides for use in energy-storage devices.However,its poor conductivity and stability limit its application.In this study,a facile method for anchoring Co3 O4-encapsulated Cu2 O nanocubes on porous carbon(PC) to form Cu2 O@Co3 O4/PC was developed.The Cu2 O@Co3 O4/PC composite exhibited superior electrochemical performance as a supercapacitor electrode material.The resultant supercapacitor delivered high specific capacitance(1096 F g^-1 at 1 A g^-1),high rate capability(83 % retention at 10 A g^-1),and excellent cycling stability(95 % retention of initial capacitance after 3000 cycles).Moreover,an asymmetric supercapacitor fabricated by coupling a Cu2 O@Co3 O4/PC positive electrode with a reduced graphene oxide negative electrode exhibited high energy density(32.1 W h kg^-1 at 700 W kg^-1).Thus,our results demonstrate that Cu2 O@Co3 O4/PC is a promising electrode material for energy-storage devices.
基金supported by the National Natural Science Foundation of China(No.51725102)Hunan Provincial Science and Technology Major Project of China(2020GK1014,2021GK2018).
文摘LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)is considered as a promising cathode for high-energy-density solid-sate Li metal battery for its high theoretical capacity.However,the high oxidizability and structural instability during charge limit its practical applications.In this work,1%(in mass)of nanosized Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP)was coated on NCM811 to enhance its electrochemical stability with a ceramic/polymer com-posite electrolyte.A robust,ultrathin(11 mm)composite electrolyte film was prepared by combining poly(vinylidene fluoride)(PVDF)with polyethylene oxide(PEO)-Li_(6.5)La_(3)Zr_(1.5)Ta_(0.5)O_(12)(LLZTO).An in-situ polymerization process was used to enhance the interface between the PVDF/PEO-LLZTO(PPL)com-posite electrolyte and the LATP-coated NCM811(LATP-NCM811).Coin-type Li|LATP-NCM811 cell with the PPL electrolyte exhibits stable cycling with an 81%capacity retention after 100 cycles at 0.5 C.Pouch-type cell was also fabricated,which can be stably cycled for 70 cycles at 0.5 C/1.0 C(80%retention),and withstand abuse tests of bending,cutting and nail penetration.This work provides an applicable method to fabricate solid-state Li metal batteries with high performance.
