Background: We report on the fabrication and characterization of Zinc Oxide (ZnO) and
Zinc Oxide Graphene (ZnO-G) composites via a simple chemical route-polyol process, using zinc nitrate
hexahydrate, ethylene glycol and reduced graphene oxide (RGO) as the precursors. The ZnO-G
composites exhibit significantly enhanced photoluminescence, which is ~ 8 times stronger than that of
ZnO samples. Such improved optical property is attributed to the contribution of plasmonic effect of
graphene in ZnO-G. Moreover, the high crystalline quality ZnO-G composites hold great potential for
dyesensitized solar cell (DSSC) applications.
Method: Graphite oxide (GO) was synthesized using modified hummers method. RGO was then synthesized
from GO by using hydrazine hydrate as a reducing agent.
Results: The short-circuit current density was increased in the ZnOG solar cell compared to that of
bare ZnO device, which is around 1.930 mA/cm2 and 0.308 mA/cm2 respectively. The conversion efficiency
of the ZnO-G DSSC was measured as 0.438%, which is ~ 7 times higher than that of ZnO
DSSC. The enhanced conversion efficiency achieved in ZnO-G DSSC resulted from the enhanced absorption
and large surface area of the composite compared to ZnO. The synthesized flakes like ZnO
and ZnO-G composites offer promising materials for DSSC applications.