Noble-metal-like catalysts of carbide and nitride for the low-temperature water–gas shift reaction: a review

The water–gas shift (WGS) reaction is critical for ensuring the purity of hydrogen in industrial hydrogen production. Due to thermodynamic limitations at high temperatures, achieving complete CO conversion at low temperatures is more feasible, although it presents a significant challenge. Currently, low-temperature WGS catalysts are mainly focused on supported noble-metal catalysts. However, an increasing number of studies have shown that transition metal carbides and nitrides, due to their noble-metal-like properties, can exhibit significant potential for achieving high performance in the low-temperature WGS reaction. In this review, we discuss the reaction performance, composition, crystal structure, preparation methods, and reaction mechanisms of the state-of-the-art transition metal carbides and nitrides. We then propose the challenges and opportunities these materials face in the low-temperature WGS reaction. We hope this review can provide valuable insights and inspiration for future research on transition metal carbides/nitrides catalysts, which can promote the development of sustainable hydrogen production technologies.