Hydrogenation of carbon dioxide: From waste to value

Atmospheric carbon dioxide concentration has been increasing in the last two decades and, as a major greenhouse gas, it has been linked to global warming and climate changes. Capture and conversion of CO2 into fuels and chemicals offer opportunities to mitigate the increasing CO2 buildup, while simultaneously adding value to CO2. The main limitation in CO2 conversion is its high thermodynamic stability, thus requiring catalysts and energy input to drive the transformation. In this minireview, we will discuss specific reaction pathways, mainly via catalytic hydrogenation and tandem processes for CO2 conversion in hydrocarbons, olefins, aromatics, and alcohols. Most steps have been studied extensively, but there are still significant challenges in developing active, selective, and stable catalysts for CO2 conversion and upgrade into molecules containing two or more carbons (C2+) suitable for large-scale CO2 valorization processes.