The present work proposes a novel strategy to fabricate an integrated architecture of gel polymer electrolyte （GPE）-nanoarray cathode for lithium-O2 batteries （LOBs）. As a proof-of-concept experiment, the photo-in...The present work proposes a novel strategy to fabricate an integrated architecture of gel polymer electrolyte （GPE）-nanoarray cathode for lithium-O2 batteries （LOBs）. As a proof-of-concept experiment, the photo-initiated in situ polymerization of GPE was carried out via incorporating the precursor solution in advance into a self- standing binder-free oxygen electrode of Co3O4 nanosheets array grown on carbon cloth （Co3O4@CC）, forming an integrated GPE-Co3O4@CC architecture. The performance of the solid-state LOBs using the GPE-Co3O4@CC assembly is greatly enhanced compared to the counterparts with a traditional cell structure, in which GPE was sandwiched by a lithium metal and a cathode. The enhanced performance is ascribed to the combination of the in situ polymerization of GPE and the versatile structure of nanoarray electrode, which results in abundant interfacial contacts between GPE and electrode. This work presents an alternative way to develop high-performance solid-state LOBs by combining the advantages of both gel polymer electrolytes and nanoarray electrodes.展开更多
Modifying electrochemical surface area(ECSA)and surface chemistry are promising approaches to enhance the capacities of oxygen cathodes for lithium-oxygen(Li-O_(2))batteries.Although various chemical approaches have b...Modifying electrochemical surface area(ECSA)and surface chemistry are promising approaches to enhance the capacities of oxygen cathodes for lithium-oxygen(Li-O_(2))batteries.Although various chemical approaches have been successfully used to tune the cathode surface,versatile physical techniques including plasma etching etc.could be more effortless and effective than arduous chemical treatments.Herein,for the first time,we propose a facile oxygen plasma treatment to simultaneously etch and modify the surface of Co_(3)O_(4)nanosheet arrays(NAs)cathode for Li-O_(2)batteries.The oxygen plasma not only etches Co_(3)O_(4)nanosheets to enhance the ECSA but also lowers the oxygen vacancy concentration to enable a Co^(3+)-rich surface.In addition,the NA architecture enables the full exposure of oxygen vacancies and surface Co^(3+)that function as the catalytically active sites.Thus,the synergistic effects of enhanced ECSA,modest oxygen vacancy and high surface Co^(3+)achieve a significantly enhanced reversible capacity of 3.45 mAh/cm^(2)for Co_(3)O_(4)NAs.This work not only develops a promising high-capacity cathode for Li-O_(2)batteries,but also provides a facile physical method to simultaneously tune the nanostructure and surface chemistry of energy storage materials.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.21673169 and 51672205)the National Key Research and Development Program of China(No.2016YFA0202602)+1 种基金the Research Start-Up Fund from Wuhan University of Technologythe Fundamental Research Funds for the Central Universities(Nos.2016IVA083 and 2017IB005)
文摘The present work proposes a novel strategy to fabricate an integrated architecture of gel polymer electrolyte （GPE）-nanoarray cathode for lithium-O2 batteries （LOBs）. As a proof-of-concept experiment, the photo-initiated in situ polymerization of GPE was carried out via incorporating the precursor solution in advance into a self- standing binder-free oxygen electrode of Co3O4 nanosheets array grown on carbon cloth （Co3O4@CC）, forming an integrated GPE-Co3O4@CC architecture. The performance of the solid-state LOBs using the GPE-Co3O4@CC assembly is greatly enhanced compared to the counterparts with a traditional cell structure, in which GPE was sandwiched by a lithium metal and a cathode. The enhanced performance is ascribed to the combination of the in situ polymerization of GPE and the versatile structure of nanoarray electrode, which results in abundant interfacial contacts between GPE and electrode. This work presents an alternative way to develop high-performance solid-state LOBs by combining the advantages of both gel polymer electrolytes and nanoarray electrodes.
基金supported by grants from the National Natural Science Foundation of China(Nos.22075219 and 51972257)the National Key Research Program of China(No.2016YFA0202602)the Research Start-Up Fund from Wuhan University of Technology.
文摘Modifying electrochemical surface area(ECSA)and surface chemistry are promising approaches to enhance the capacities of oxygen cathodes for lithium-oxygen(Li-O_(2))batteries.Although various chemical approaches have been successfully used to tune the cathode surface,versatile physical techniques including plasma etching etc.could be more effortless and effective than arduous chemical treatments.Herein,for the first time,we propose a facile oxygen plasma treatment to simultaneously etch and modify the surface of Co_(3)O_(4)nanosheet arrays(NAs)cathode for Li-O_(2)batteries.The oxygen plasma not only etches Co_(3)O_(4)nanosheets to enhance the ECSA but also lowers the oxygen vacancy concentration to enable a Co^(3+)-rich surface.In addition,the NA architecture enables the full exposure of oxygen vacancies and surface Co^(3+)that function as the catalytically active sites.Thus,the synergistic effects of enhanced ECSA,modest oxygen vacancy and high surface Co^(3+)achieve a significantly enhanced reversible capacity of 3.45 mAh/cm^(2)for Co_(3)O_(4)NAs.This work not only develops a promising high-capacity cathode for Li-O_(2)batteries,but also provides a facile physical method to simultaneously tune the nanostructure and surface chemistry of energy storage materials.
