Tailoring power conversion efficiency of dye sensitized solar cell based on ZnO/g-C3N4 hybrid photoelectrodes via microwave irradiation route

Abstract

Herein, first time we report the high performance dye sensitized solar cell (DSSCs) based on sensibly designing g-C3N4 modified by ZnO nanoparticles as photoanodes synthesized by one step facile microwave irradiation route. Formation of the hybrid composites and its optical properties were confirmed via X-ray diffraction (XRD), Raman, Energy dispersive X-ray (EDAX), high-resolution transmission electron microscopy (HRTEM), UV–Vis absorption and photoluminescence spectra analysis. Hexagonal crystalline structure with individual spherical shaped nanoparticles with size in the range of 15–25 nm is observed in bare ZnO was homogeneously exfoliated on the g-C3N4 sheets. Enhancing the light absorption property in the visible light region and diminish the recombination process of the electron-hole pairs was identified by UV and PL results. The J-V characteristic was studied the fabricated sandwich type solar cell device for various rational photoanodes. The optimized ZnO/g-C3N4 (15 wt% ZnO loaded g-C3N4) photoanode delivers a high photo-conversion efficiency (PCE) of 9.21%, which 4.2 times better than that of bare ZnO (2.19%). The photovoltaic based mechanism of the proposed photoelectrode was also discussed in detail.