Metal Alloy Catalysts for Thermo-Catalytic Hydrogenation of CO2 to Fuels and Chemicals

The extensive use of fossil fuels has raised a series of environmental issues due to the drastic rise in atmospheric CO 2 levels. Although the Earth has natural processes for sequestering CO 2 , the use of renewable energy for the direct hydrogenation of CO 2 to value-added chemicals and fuels is a more profitable strategy to reduce CO 2 . While other hydrogenation technologies exist, the thermo-catalytic process is particularly attractive owing to its high efficiency and selectivity toward targeted products. Due to the high stability of CO 2 , the thermo-catalytic hydrogenation of CO 2 requires careful optimization of both the catalytic properties and the reaction conditions. Structural tuning of catalytic properties includes an effective metal alloying strategy, because alloying alters metal surfaces’ chemical properties, creating new active sites for enhanced catalytic activity. To be industrially relevant, the designed metal alloy catalysts should present outstanding performance, stability, and selectivity. Reaction conditions, such as the reactor design, are also paramount to the efficiency of the hydrogenation process as most catalysts can develop catalytic hotspots, leading to uncontrollable kinetics and skewed product distributions. Several catalysts are also susceptible to deactivation at high temperatures, thus the computation aspect of the CO 2 hydrogenation is central to understanding several reaction parameters for the design of efficient, stable, and selective metal alloy catalysts. The thermo-catalytic hydrogenation of CO 2 has resulted in numerous research outputs, pilot and demonstration-scale plants, commercialization prospects, and technological advancements, showing its efficiency in profitably reducing the global carbon footprint.