3-Earth-abundant Fe_1-xS@S-doped graphene oxide nano–micro composites as high-performance cathode catalysts for green solar energy utilization:fast interfacial electron exchange

【作者】 李月强； 尹杰； 张宪玺； 周华伟； 王术皓； 单位:；

【机构】 聊城大学化学化工学院山东省化学储能与新型电池技术重点实验室；

【摘要】 Herein,we prepared a nano–micro composite（NMC） of Fe_1-xS nanoparticles decorated on sulfur-doped graphene oxide（S-GO） sheets(namely,Fe_1-xS@S-GO–NMC) to be used as a cathode in dye-sensitized solar cells（DSCs）.The GO effectively inhibit the aggregation of Fe_1-xS nanoparticles.Notably,DSCs based on an Fe_1-x1 x S@S-GO–NMC cathode achieved a high solar-to-electrical conversion efficiency up to 7.23%.The conversion efficiency is,to our knowledge,one of the highest efficiencies for DSCs based on an FeS or FeS₂ cathode.Although the Fe_1-xS@S-GO–NMC exhibited a low thermodynamic possibility for redox reactions,it showed a higher kinetic rate than that of Pt for the charge transfer between the reaction medium and the cathode.This indicates that a fast electron exchange process occurs at the interface between the reaction and the cathode.The value of the time constant（s） corresponding to the charge exchange resistance based on Fe_1-xS@S-GO–NMC（0.0215 ms） was smaller than that obtained with Pt（0.261 ms）.Therefore,we ascribed the superior performance of the photoelectrochemical device based on Fe_1-xS@S-GO–NMC to its good electrocatalytic performance.The results are of great interest for fundamental research and for practical applications of FeS and FeS₂ and their composites in the solar splitting of water,artificial photoelectrochemical cells,and electrocatalysts.更多还原

【Abstract】 Herein,we prepared a nano–micro composite（NMC） of Fe_1-xS nanoparticles decorated on sulfur-doped graphene oxide（S-GO） sheets(namely,Fe_1-xS@S-GO–NMC) to be used as a cathode in dye-sensitized solar cells（DSCs）.The GO effectively inhibit the aggregation of Fe_1-xS nanoparticles.Notably,DSCs based on an Fe_1-x1 x S@S-GO–NMC cathode achieved a high solar-to-electrical conversion efficiency up to 7.23%.The conversion efficiency is,to our knowledge,one of the highest efficiencies for DSCs based on an FeS or FeS₂ cathode.Although the Fe_1-xS@S-GO–NMC exhibited a low thermodynamic possibility for redox reactions,it showed a higher kinetic rate than that of Pt for the charge transfer between the reaction medium and the cathode.This indicates that a fast electron exchange process occurs at the interface between the reaction and the cathode.The value of the time constant（s） corresponding to the charge exchange resistance based on Fe_1-xS@S-GO–NMC（0.0215 ms） was smaller than that obtained with Pt（0.261 ms）.Therefore,we ascribed the superior performance of the photoelectrochemical device based on Fe_1-xS@S-GO–NMC to its good electrocatalytic performance.The results are of great interest for fundamental research and for practical applications of FeS and FeS₂ and their composites in the solar splitting of water,artificial photoelectrochemical cells,and electrocatalysts.更多还原