Mn-Promoted CuZnAl Oxide for Enhanced Low-Temperature Reverse Water–Gas Shift Reaction

The reverse water–gas shift (RWGS) reaction is crucial for CO2 utilization toward carbon neutrality. However, its efficiency under mild conditions is limited by low-temperature activity and rapid deactivation from metal sintering in conventional catalysts, including the cost-effective but thermally unstable Cu-based systems. In this work, the introduction of Mn into CuZnAl catalysts was demonstrated to significantly enhance their performance in the low-temperature RWGS reaction by promoting more oxygen vacancy formation. MnCuZnAl-Red catalysts achieve superior 26% CO2 conversion and 98% CO selectivity at 400 °C, with a CO formation rate of 422 mmol gcat–1 h–1. Characterization confirms that Mn enhances CO2 adsorption and activation by generating abundant oxygen vacancies. In-situ Fourier infrared (FT-IR) spectroscopy reveals a surface associative pathway. This work highlights Mn’s role in enhancing RWGS activity through tailored oxygen chemistry.