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. [Display omitted] New catalytic technologies to convert the greenhouse gas CO2 into useful products by renewable energy is becoming more important than ever due to recent alarming events attributable to climate change. Among various products from C1 chemistry, more attention should be paid to the hydrogenation of CO2 to higher alcohols since they are value-added chemicals as fuel additives, reaction solvents, and intermediates. However, higher alcohol synthesis is severely impeded by the difficulties in the chemical inertness of CO2 and complexity in various reaction routes and the uncontrollability of C–C coupling from untamed surface moieties. Development of highly effective and selective catalysts remains a great challenge to the production of higher alcohols. Moreover, further in-depth comprehension of the reaction mechanisms offers practical guidance to new design of catalyst systems. This review provides a new prospect for future research on catalytic CO2 hydrogenation to higher alcohols. Higher alcohol synthesis from CO2 hydrogenation is a promising and challenging way to realize the efficient utilization of CO2 resources. Despite recent progress, there is still a lack of deeper understanding in this field. This review focuses on the recent advances in heterogeneous catalytic hydrogenation of CO2 to higher alcohols, in terms of catalyst families, reaction mechanisms, and the rational design of ideal catalysts. This will prov