Unravelling the Cu-Co nanoparticle synergy over Ceria-Zirconia support toward efficient reverse water gas shift (RWGS) conversion under H2 lean conditions
Anuradha Vijay Jagtap, Mahesh Kumar Bamnia, Ashakiran Maibam, J. Bajpai, Sharad Gupta, S. C. Thomas, Niteen B. Dabke, C. P. Vinod
Abstract
CO 2 emissions leading to global warming and environmental and socio-economic issues have propelled the research community to develop technologies capable of capturing and converting CO 2 into valuable products. Controlling the selectivity toward platform molecules like CO, methanol, or methane is a fundamental challenge in CO 2 hydrogenation. Supported cobalt nanoparticles are known for hydrocarbon production through Fischer-Tropsch (FT) reaction, and Cu-based catalysts are known for reverse water gas shift (RWGS) reaction. Here, we show that d-band centre can be carefully modulated by making bimetallic combinations of Cu and Co for a highly active RWGS catalyst. An oxygen vacancy-rich nanostructured ceria-zirconia (CZ) support with Cu nanoparticles (2 wt%) modified with as low as 0.05 wt% Co shows excellent conversion for CO 2 hydrogenation and selectivity for CO below 500 °C. The optimized catalyst shows CO 2 conversion even under hydrogen lean conditions (H 2 /CO 2 ratio 0.5:1), with a breakthrough rate of 206023 mmol/g metal /h for CO at 600 °C, having H 2 utilization of 80% for the RWGS process.