Anchoring PdAu nanoclusters inside aminated metal-organic framework for fast dehydrogenation of formic acid

Liquid sunshine formic acid (FA), which is obtainable through CO 2 hydrogenation with green H 2 or biomass processing, is regarded as a prospective liquid organic hydrogen carrier (LOHC) owing to its high volumetric capacity (53 g H 2 L −1 ), stability, and renewability. The search for effective catalysts to produce H 2 from additive-free FA under ambient conditions is necessary but remains a challenge. Herein, highly dispersed and ultrafine PdAu nanoclusters (NCs) (1.2 nm) anchored by the aminated metal–organic framework (NH 2 -MIL-101) were successfully fabricated using a facile wet-chemical method and employed as a superior catalyst for formic acid dehydrogenation (FAD). The resulting PdAu/NH 2 -MIL-101 catalyst demonstrates 100 % H 2 selectivity and superior performance with a turnover frequency value reaching 2921.0 h −1 at 323 K without any additive. Under similar conditions, this value is higher than the majority of published MOF-based FAD heterogeneous catalysts. The superior performance of PdAu/NH 2 -MIL-101 originates from a synergistic combination of the promoting effect of amino groups, the effective electronic coupling of Pd and Au, and the strong metal-support interaction between PdAu NCs and NH 2 -MIL-101, which promote the formation of reactive PdAu NCs and thus greatly improve catalytic performance. This work may provide important inspiration for developing highly efficient catalysts and strongly promote FA as a promising LOHC for chemical H 2 storage.