Advances in higher alcohol synthesis from CO2 hydrogenation

Converting the greenhouse gas CO2 into higher alcohols (HAs) via hydrogenation reaction requires more attention in C1 chemistry because the C2+ alcoholic products are value-added chemicals as fuel additives, reaction solvents, and intermediates. However, the chemical inertness of CO2, complexity in various reaction routes, and uncontrollability of C–C coupling from untamed surface moieties in higher alcohol synthesis (HAS) make this approach very challenging to achieve. In this review, we summarize and analyze the recent advances in catalytic HAS from direct CO2 hydrogenation. The first section highlights the potential promising catalyst families, including a noble-metal class of catalysts, modified Co-based catalysts, modified Cu-based catalysts, and Mo-based catalysts with the roles of promoters and supports specified in each case. The second section reviews the possible reaction mechanisms based on previous experimental results. The rational design of ideal catalyst systems for this reaction is discussed in the third section.