Tuning the selectivity of photothermal CO2 hydrogenation through photo-induced interaction between Ni nanoparticles and TiO2

Abstract

Photothermal CO2 hydrogenation into value-added chemicals driven by abundant solar energy is a promising and sustainable approach for achieving carbon neutralization. Herein, we demonstrate the photo-induced interaction between Ni nanoparticles and TiO2 support (Ni@TiO2) for maneuvering the selectivity of photothermal CO2 hydrogenation. According to experimental characterizations and theoretical simulations, the formed strong metal-support interaction between Ni and TiO2 can significantly enhance the adsorption of key intermediate *CO for further hydrogenation, thus tuning the CO2 hydrogenation pathway toward CH4. Consequently, the Ni@TiO2 catalyst exhibits a CH4 production rate of 286.5 mmol gcat−1 h−1 with an 81.8% selectivity under full-spectrum solar light irradiation. Moreover, in situ experimental characterizations and theoretical calculations suggest that photothermal CO2 hydrogenation over Ni@TiO2 undergoes a stepwise hydrogenation pathway to methane. This work offers insights into a simple approach for designing efficient nonprecious metal-based CO2 methanation catalysts.