RGO-loaded flower-like ZnCo2O4 nanohybrid as counter electrode for dye-sensitized solar cells

Reduced graphene oxide (RGO)-loaded flower-like ZnCo2O4 nanohybrid (ZnCo2O4/RGO) was prepared and then used as counter electrode (CE) in dye-sensitized solar cells (DSSCs). Scanning electron microscopy showed that the flower-like structure of ZnCo2O4 was made up of a large number of thin nanosheets and that the RGO sheets reunited with ZnCo2O4 together commendably. The results and analysis illustrated that the distinctive ZnCo2O4 structure provided numberous catalytic reaction sites and that the RGO sheets served as a guide way to accelerate the transmission of electrons. Benefited from the synergetic effect of ZnCo2O4 and RGO, the ZnCo2O4/RGO nanohybrid exhibited excellent electrocatalytic performance. Finally, a competitive power conversion efficiency (PCE) of 7.22% was achieved for the DSSCs based on the ZnCo2O4/RGO nanohybrid CE.