Tri-metallic AuPdIr nanoalloy towards efficient hydrogen generation from formic acid

Formic acid (FA), as a safe and renewable hydrogen storage material, attracts extensive attention. Herein, an efficient catalyst Au 0.35 Pd 0.5 Ir 0.15 nanoalloy supported on NH 2 -N-rGO has been successfully synthesized and applied for hydrogen generation from FA. It is found by density function theory (DFT) calculation that addition of Ir into AuPd alloy can change the initial adsorption configuration of HCOOH* and thus reduce the energy barrier of rate determining step (RDS) of FA dehydrogenation. As a result, Au 0.35 Pd 0.5 Ir 0.15 /NH 2 -N-rGO displays 100% conversion, 100% selectivity even after 150 days for FA dehydrogenation at 298 K, and the initial turnover frequency (TOF) can reach the recorded value (12781.2 h −1 ) without any additives. More interestingly, it is proved to be a universal method to design the effective catalysts for hydrogen generation from FA by the high activities of other tri-metallic alloys with addition of other high γ elements (such as Pt, Rh, and Ru). Hydrogen is a clean and important energy source to replace fossil fuels. Au 0.35 Pd 0.5 Ir 0.15 /NH 2 -N-rGO catalyst with an excellent initial TOF of 12781.2 h −1 is prepared and tested, which can remain highly active even after 150 days under ambient condition. And DFT calculations prove that addition of a high surface energy element such as Ir, and others can modify the reaction pathway towards FA dehydrogenation, leading to the improvement of catalytic activity compared with AuPd. • The ultra-fine AuPdIr nanoparticles (~2.6 nm) are synthesized. • The catalyst of AuPdIr has excellent initial TOF value (12781.2 h −1 ) and outstanding stability (150 days). • The nature behind the superior performance was clarified by the DFT calculation.