Hydrothermal Preparation of Ni3S4/CoS2 Composite Electrocatalytic Materials for High Performance Counter Electrodes of Dye-Sensitized Solar Cells

Abstract

A facile one step synthetic hydrothermal route was used to fabricate the Pt free Ni3S4/CoS2 heterostructure counter electrode and study the photovoltaic characteristics constructed by the sandwich type DSSC. The heterostructure combination of Ni3S4 nanoparticles onto flexible CoS2 nanosheets is crucial for achieving the in high I3− reduction in the electrocatalytic activity. SEM and TEM results suggest that Ni3S4 has individual nanoparticles sizes in the range of 20–30 nm was uniformly decorated on the CoS2 nanosheets. When the combination of Ni3S4/CoS2 heterostructure CE delivered a high power conversion efficiency of 10.1% than that of sole Ni3S4 (5.8%) and CoS2 (4.5%). The superior PCE of the composite is due to the heterostructure, mesoporous nature and high surface area (103.4 m2/g). Due to the high photovoltaic and electrocatalytic activity of Ni3S4/CoS2 heterostructure can be useful for Pt free DSSCs, energy conversion and storage device applications.