Anti‐Sintering Ni‐W Catalytic Layer on Reductive Tungsten Carbides for Superior High‐Temperature CO₂ Reduction

Abstract

AbstractThe reverse water‐gas shift (RWGS) reaction stands out as a promising approach for selectively converting CO2 into CO, which can then be upgraded into high‐value‐added products. While designing high selectivity and stability catalysts for RWGS reaction remains a significant challenge. In this study, an efficient and ultra‐stable Ni‐W catalytic layer on reductive WC (NiAWC) is designed as an anti‐sintering catalyst for superior high‐temperature RWGS reaction. Benefiting from the unique structures, the NiAWC catalyst exhibits exceptionally high performances with a CO production rate of 1.84 molCO gNi−1 h−1 and over 95% CO selectivity, maintaining stability for 120 h at 500 °C. Even after 300 h of continuous testing at 600 °C and five aging cycles at 800 °C, the activity loss is only 0.34% and 0.83%, respectively. Unlike the conventional mechanism in RWGS reaction, it is demonstrated that the Ni‐W limited coordination can stabilize the Ni sites and allow a pre‐oxidation of Niδ+ by CO, which produces an O* electronic reservoir and hinders the charge transfer from Ni to W‐O, thereby avoiding the dissolution of Ni atoms. The design of new, efficient, and selective catalysts through metal‐substrate synergistic effects is suggested to offer a promising path to engineering superior thermal catalysts.