Ultrasonic-assisted synthesis of ZnO nano particles decked with few layered graphene nanocomposite as photoanode in dye-sensitized solar cell

ZnO decked few layered graphene (FLG; 1.0, 2.0 and 3.0 wt%) nanocomposites were synthesized by simple and cost effective way using ultrasonic-assisted synthesis method. The morphological, optical and structural properties of as-synthesized nanocomposites were analyzed by field emission scanning electron microscopy and high-resolution transmission electron microscopy, UV–Visible spectroscopy with diffuse reflectance, fourier transform infrared spectroscopy, X-ray diffractometry and ramam spectroscopy. The synthesized FLG (1.0, 2.0 and 3.0 wt%)/ZnO nanocomposite were used as photoanode materials and deposited as thin films on fluorine-doped tin oxide substrate by doctor blade method for dye-sensitized solar cell (DSSC) fabrication. By varying the FLG weight percentage (1.0, 2.0 and 3.0 wt%) in ZnO nanocomposites the power conversion efficiency (PCE) in DSSC was optimized. Using N719 dye the current density–voltage (J–V) was measured under AM 1.5G, 100 m W/m² of the solar simulator. Results obtained after optimization showed PCE of 4.61% at the suitable FLG (1.0 wt%)/ZnO, compared to ZnO and other photoanodes.