Conceptual unification of mechanism-guided catalyst design for CO2 conversion to C1 products in thermal and plasma catalysis

Abstract

Carbon dioxide (CO2) reduction to value-added chemicals for sustainable and clean energy is hindered by its considerable ionization potential (IP) and negative adiabatic electron affinity (EA), which makes CO2 a chemically inert molecule, leading to its challenging and unfavorable conversion under ambient conditions. To cope with this challenge, novel catalysts have been developed to lower the activation energy for CO2 conversion reactions. However, the low activity, selectivity, and deactivation of catalysts limit their industrial applications. This scenario demands the development of next-generation, highly active, selective, and long-term stable catalysts for CO2 conversion based on the reaction mechanism and microkinetics. This review summarizes and unifies the current catalyst design concepts for the thermochemical CO2 conversion to C1 products via heterogenous catalysis. In addition, recommendations are made to leverage thermal-catalysis knowledge to design plasma-activated catalysts. Four reactions were reviewed and analyzed for producing single-carbon (C1) organic products, including reverse water gas shift (RWGS) reaction, dry reforming of methane (DRM), CO2 methanation, and CO2 hydrogenation. Each section focuses on one reaction to elaborate on the reaction mechanism and current status for experimental and computational-based development of catalysts, including unsupported mono-metals, supported mono- and bimetallic catalysis, and transition carbide catalysts, depending on the reaction followed by the potential causes of catalyst deactivation. Finally, directions for future development are outlined with recommendations to translate the thermal catalysis concepts at a specific level for a rational catalyst design to catalyze CO2 conversion to C1 products under a non-thermal plasma (NTP) catalytic system.