Reaction network of CO2 hydrogenation into C1–2 oxygenates and its BEP relationships

Abstract

Although copper is one of the most common components in catalysts for CO₂ conversion into valuable C₂₊ chemicals, a clear and systematic mechanistic explanation of its unique properties in these processes is lacking. Herein, we address this challenge by introducing a novel ansatz to rationally construct catalytic reaction networks and account for realistic active sites on catalyst nanoparticles, applied here to CO₂ hydrogenation into C₁ and C₂ oxygenates, explaining the formation of frequently observed reaction intermediates. We also provide a comparative mechanistic analysis of CO₂ hydrogenation on a stronger-adsorbing metal widely used in hydrogenation reactions, Pd. Furthermore, we present a refined approach to Brønsted–Evans–Polanyi relationships tailored to structural characteristics of transition states. Our approach facilitates further exploration of CO₂ hydrogenation on transition metal-based catalysts, deepening our understanding of the underlying reaction mechanism. This theoretical framework not only elucidates the intricate kinetics of CO₂ hydrogenation but also establishes a versatile foundation for rational catalyst design across catalytic domains. This study highlights the unique activity of Cu in various hydrogenation and C–C coupling steps. Unlike scarce metals that require resource-intensive extraction, Cu reduces the environmental impact and costs of CO₂ conversion technologies. Clarifying its unique role in converting CO₂ into valuable C₂₊ chemicals moves us closer to balancing economic growth and environmental protection.