l-Lysine mediated synthesis of platinum nanocuboids and their electrocatalytic activity towards ammonia oxidation

Abstract

Well-defined platinum nanocrystals with a cuboid-like shape (Pt nanocuboids) were synthesized in high yields by the simple hydrothermal reduction of Pt(II) precursors with formaldehyde (HCHO) solution in the presence of L-lysine and polyvinyl pyrrolidone (PVP). The influential effects of several important experimental parameters on the shape of Pt nanocrystals were systematically investigated, demonstrating that L-lysine and oxidative etching were critical to the morphological control and evolution of Pt nanocuboids. Due to the unique orientation and size effects, the as-prepared Pt nanocuboids exhibited significantly enhanced catalytic activity and stability towards the ammonia oxidation reaction (AOR) in comparison with commercial Pt black catalysts.