Selective photothermal reduction of CO2 to CH4 via the synergistic effect of Ni-nanoparticle@NiO-nanosheet/V2C-MXene catalyst

Abstract

Photothermal catalytic carbon dioxide (CO2) reduction has attracted increasing research attention as a promising method for recycling CO2 and producing renewable energy. However, it remains a challenge in the improvement of catalytic activity with regulated product selectivity in view of practical applications. Herein, we develop the two-dimensional layered V2C MXene (VC) supported Ni nanoparticle and NiO nanosheet (Ni@NiO/VC) composite as an efficient catalyst for selective photothermal reduction of CO2 to CH4. The optimal 0.8Ni@NiO/VC catalyst exhibits 48.1 % CO2 conversion with an evolution rate of 33.2 mmol/gcat/h and 99.2 % selectivity for CH4 production under a 300 W full-arc xenon lamp irradiation. Moreover, a long-term cyclic photothermal CO2 reduction reaction demonstrates the excellent stability of 0.8Ni@NiO/VC. The enhanced photothermal CO2 reduction activity with a high CH4 selectivity could be attributed to the large specific surface area and excellent photothermal effect of V2C MXene, and the synergistic effect of Ni and NiO on adsorption/activation of H2 and CO2 molecules. This work provides a feasible strategy for the construction of efficient photothermal CO2 reduction catalyst by properly incorporating transition metal nanoparticles and metal oxide with a suitable MXene.