Design of Cu/MoOx for CO2 Reduction via Reverse Water Gas Shift Reaction

Abstract

CO2 reduction to CO as raw material for conversion to chemicals and gasoline fuels via the reverse water–gas shift (RWGS) reaction is generally acknowledged to be a promising strategy that makes the CO2 utilization process more economical and efficient. Cu-based catalysts are low-cost and have high catalytic performance but have insufficient stability due to hardening at high temperatures. In this work, a series of Cu-based catalysts supported by MoOx were synthesized for noble metal-free RWGS reactions, and the effects of MoOx support on catalyst performance were investigated. The results show that the introduction of MoOx can effectively improve the catalytic performance of RWGS reactions. The obtained Cu/MoOx (1:1) catalyst displays excellent activity with 35.85% CO2 conversion and 99% selectivity for CO at 400 °C. A combination of XRD, XPS, and HRTEM characterization results demonstrate that MoOx support enhances the metal-oxide interactions with Cu through electronic modification and geometric coverage, thus obtaining highly dispersed copper and more Cu-MoOx interfaces as well as more corresponding oxygen vacancies.