Highly Efficient Hydrogen Production via the Hydrolysis of Ammonia Borane over Nanostructured Pd-Cu Nanoparticles Supported on PDA-coated Graphene

摘要

Palladium (Pd), copper (Cu) bimetallic alloy nanoparticles immobilized onto a PDA-coated graphene support (Pd-Cu/PDA/RGO) hybrid was synthesized through co-reduction of K2PdCl4 and Cu(NO3)(2). The Pd to Cu ratio was rationally controlled to obtain the optimum Pd-Cu/PDA/RGO catalyst. The as-prepared catalyst demonstrated good catalytic activity for hydrogen production by hydrolysis of ammonia borane, high turnover frequency (TOF) of 37.41 mol H-2 per mol Pd-1 min(-1) at 298 K and a low activation energy (E-a) of 47.97 kJ mol(-1) were accomplished, these metrics were superior to that of Pd-Cu/RGO nanocatalysts. The comparative results indicate that the PDA-coated graphene (PDA/RGO) support is pivotal for the catalytic activity of Pd-Cu/PDA/RGO for hydrolysis of ammonia borane. The PDA modified onto GO surface effectively disperse the alloy particles, therefore ensure more catalytic active sites responsible for ammonia borane hydrolysis. The tight anchoring of alloy nanoparticles also enabled excellent cyclic stability, 67.7 of its initial catalytic activity could be maintained after ten cycles. The current work demonstrates the potential of Pd-Cu/PDA/RGO in active and durable ammonia borane hydrolysis for hydrogen production.