Direct Synthesis of Pd2+-Rich Palladene Aerogels as Bifunctional Electrocatalysts for Formic Acid Oxidation Reaction and Oxygen Reduction Reaction

In this work, we developed a direct strategy to fabricate Palladene (i. e. Palladium metallene) aerogels and propose a temperature-dependent growth mechanism. Besides the typical three-dimensional networks and wrinkled surface morphologies, the as-prepared $$ aerogel is endowed with abundant Pd²⁺. The as-prepared $$ aerogel exhibits an excellent mass activity in the formic acid oxidation reaction and a good half-wave potential in the oxygen reduction reaction in comparison with Pd/C and a Pd aerogel. This work expands the range of metal aerogels from the perspective of the building block units and demonstrates a direct approach to fabricate highly promising bifunctional electrocatalysts for fuel cells.