Photothermal catalytic activity and mechanism of LaNixCo1−xO3(0 ≦ x ≦ 1) perovskites for CO2 reduction to CH4 and CH3OH with H2O

A series of LaNi x Co 1− x O 3 perovskites were synthesized by sol–gel combustion method, the photothermal catalysis of CO 2 and H 2 O into CH 4 and CH 3 OH was investigated systematically. The crystal structure, surface area, oxygen vacancies, band structures and catalytic performance of LaNi x Co 1− x O 3 perovskites were characterized thoroughly in order to understand the design principle of the material for such a photothermal catalysis of CO 2 and H 2 O. With the change of x value, the best catalytic performance was achieved at x = 0.4 and the accumulated yield of CH 4 and CH 3 OH can reach 678.57, 20.83 μ molg −1 in 6 h, which were 3.4 and 3.8, 1.9 and 2.2 times of that of two end composition, LaCoO 3 and LaNiO 3 under the same condition. For LaNi 0.4 Co 0.6 O 3 , the surface area reached a maximum concentration of oxygen vacancy while the band gap reached a minimum of 1.42 eV. It is evident that the formation of solid solution between LaMO 3 (M = transition metals) compounds can be a general strategy for the new catalyst design.