Developing efficient counter electrodes(CEs)and quantum dots made of earth-abundant and non-toxic elements is essential but still challenging for quantum dot-sensitized solar cells(QDSSCs).Here,we report a facile stra...Developing efficient counter electrodes(CEs)and quantum dots made of earth-abundant and non-toxic elements is essential but still challenging for quantum dot-sensitized solar cells(QDSSCs).Here,we report a facile strategy to prepare self-supported and robust CoS_2and NiS nanocrystals-assembled nanosheets directly grown on carbon paper(MS_xNS@CP)as efficient counter electrodes for QDSSCs.Such CEs integrate the merits of fast electron transfer from interconnected conductive scaffold,efficient mass transfer from hierarchically vertical nanosheet on 3D open substrate,as well as abundant highly active catalytic sites from metal sulphide nanocrystal units.As a result,QDDSCs based on such CoS_2NS@CP and NiS NS@CP CEs achieve a PCE of8.88%and 7.53%,respectively.The detailed analyses suggest that CoS_2NS@CP has the highest catalytic activity and shows the lowest charger transfer resistance,leading to the highest PCE.These findings may inspire the design and exploration of other self-supported efficient CEs by integrating highly active catalysts onto 3D conductive networks for efficient QDSSCs.展开更多
基金supported by the National Natural Science Foundation of China (21573249, 51732004)the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB12020100)
文摘Developing efficient counter electrodes(CEs)and quantum dots made of earth-abundant and non-toxic elements is essential but still challenging for quantum dot-sensitized solar cells(QDSSCs).Here,we report a facile strategy to prepare self-supported and robust CoS_2and NiS nanocrystals-assembled nanosheets directly grown on carbon paper(MS_xNS@CP)as efficient counter electrodes for QDSSCs.Such CEs integrate the merits of fast electron transfer from interconnected conductive scaffold,efficient mass transfer from hierarchically vertical nanosheet on 3D open substrate,as well as abundant highly active catalytic sites from metal sulphide nanocrystal units.As a result,QDDSCs based on such CoS_2NS@CP and NiS NS@CP CEs achieve a PCE of8.88%and 7.53%,respectively.The detailed analyses suggest that CoS_2NS@CP has the highest catalytic activity and shows the lowest charger transfer resistance,leading to the highest PCE.These findings may inspire the design and exploration of other self-supported efficient CEs by integrating highly active catalysts onto 3D conductive networks for efficient QDSSCs.