Co3O4/graphene nanocomposites were synthesized
via sonochemical method, and its application as a
counter electrode (CE) for dye-sensitized solar cell (DSSC)
was demonstrated. The prepared Co3O4/graphene
nanocomposites were characterized by X-ray diffraction,
scanning electron microscopy, and UV–Vis absorption
spectroscopy. The results of SEM showed that Co3O4
nanoparticles deposited on the graphene sheets as spacers
to keep the neighboring sheets separated. The Co3O4 have
diameters ranging from 16 to 43 nm. The influence of the
Co3O4 content on the photovoltaic performance of dyesensitized
solar cell was investigated. It was found that the
performances of Co3O4/graphene composites are better
than that of graphene-based DSSCs. The Co3O4/graphene
composite CE with 80 % Co3O4 content exhibits the best
conversion efficiency (PCE) of 2.1 %.