Transition metal oxides in CO2 driven oxidative dehydrogenation: Uncovering their redox properties

Abstract

Extensive research efforts have been devoted to using greenhouse gas CO2 in upgrading bio-derived feedstock to value-added chemicals using the oxidative dehydrogenation route (CO2-ODH) with low-energy input. To realize the effective deployment of CO2-ODH at an industrial scale, it is imperative to advance the development of robust catalysts that can selectively catalyze C-H over C-C bonds, while simultaneously demonstrating thermodynamic stability to coke formation or sintering. Transition metal-based catalysts exhibit significant potential for being highly selective and reactive in the simultaneous conversion of CO2 and hydrocarbons, owing to their surface reducibility, well-balanced acid/base properties, and dynamic oxygen storage capacity. To stimulate further optimization, it's crucial to discover key design principles, potential trends and descriptors, and effective strategies to fine-tune the catalyst materials. This review comprehensively examines experimental and theoretical research aimed at pinpointing the key catalytic characteristics that affect selectivity in transition metal-based mono, bi, and multimetal oxides. It covers aspects like combinations of active metals and supports, effects of composition and alloying, interfacial structures, adsorption strengths, dynamics of in-situ restructuring, defect creation, surface morphology, and electronic properties, among others. We wrap up by suggesting approaches to overcome present obstacles in catalyst design and reactor technology, potentially bridging the lab-to-industry gap in this domain.

Keywords

• CO2 oxidative dehydrogenation (CO2-ODH)
• Transition metals
• Redox cycling
• Catalyst deactivation
• Lattice oxygen