Towards Hydrogen Storage through an Efficient Ruthenium-Catalyzed Dehydrogenation of Formic Acid

Hydrogen is of fundamental importance for the construction of modern clean-energy supply systems. In this context, the catalytic dehydrogenation of formic acid (FA) is a convenient method to generate H₂ gas from an easily available liquid. One of the issues associated with current catalytic dehydrogenation systems is insufficient stability. Here, we present a robust and recyclable system for FA dehydrogenation by combining a ruthenium 1,1,1-tris(diphenylphosphinomethyl)ethane complex and aluminum trifluoromethanesulfonate (Al(OTf)₃ ). This robust system allows steady H₂ production under pressure and recycling for an additional 14 runs without any apparent loss of activity (turnover frequencies up to 1920 h^-1 , turnover numbers up to 20 000). Notably, the catalyst can also be used for the dehydrogenation of formates and the reverse hydrogenation of bicarbonates and CO₂ .