Synthesis of isolated ZnO nanorods on introducing g-C₃N₄ for improved photoelectrocatalytic methanol production by CO₂ reduction

The photoelectrocatalytic (PEC) CO₂ reduction into fuels has been developed as a prospective approach to resolve the environmental and energy concerns. Herein, a composite catalyst comprising ZnO nanorods dispersed on the g-C₃N₄ surface (g-C₃N₄/ZnO) was successfully obtained by simple ZnO seed layer formation and then hydrothermal processes. The synthesized and characterized g-C₃N₄/ZnO catalytic composite showed 2.8 times enhanced photocurrent density at −1 V applied potential than the bare g-C₃N₄. The g-C₃N₄/ZnO catalyst exhibited 2.86 times enhanced the PEC CO₂ reduction to methanol than the prepared bare ZnO catalyst. The catalyst's enhanced PEC CO₂ reduction performance was ascribed to the high surface area, and higher generation and lower recombination of e⁻/h⁺ pairs. For the first time, this study showed the enhanced methanol production by the PEC reduction of CO₂ over the prepared g-C₃N₄/ZnO catalytic composite.