Reviews on Homogeneous and Heterogeneous Catalysts for Dehydrogenation and Recycling of Formic Acid: Progress and Perspectives

The environmental pollution caused by the excessive use of fossil fuels makes people pay more attention to the use of green energy. Clean and efficient hydrogen energy has a wide range of practical applications in today's society. Accordingly, mature and sustainable hydrogen storage technologies have received much attention. In recent years, formic acid has attracted tremendous attention as an efficient liquid organic hydrogen carrier. The easy storage and transportability of formic acid, its efficient hydrogen production, and its recyclability make it a promising development. This review summaries the reports and studies on formic acid dehydrogenation and hydrogen storage in recent years. Mainly studied are the homogeneous and heterogeneous catalysts for formic acid dehydrogenation and CO2 hydrogenation reactions. The reaction pathways and reaction mechanisms of formic acid dehydrogenation are also presented. In addition, direct formic acid fuel cells are presented in order to understand the practical applications of formic acid.