Electrochemically Shape-Controlled Synthesis in Deep Eutectic Solvents—A New Route to Prepare Pt Nanocrystals Enclosed by High-Index Facets with High Catalytic Activity

In the present paper, we have developed for the first time the electrochemically shape-controlled synthesis in deep eutectic solvents (DESs) for the preparation of Pt nanocrystals enclosed by high-index facets. Monodispersed concave tetrahexahedral Pt nanocrystals (THH Pt NCs) have been prepared through this new route. The concave THH Pt NCs were characterized by SEM, TEM, and AFM. The as-prepared concave Pt NCs are bounded with {910} and vicinal high-index facets, which exhibit superior catalytic activity and stability to those of the commercial Pt black catalyst for ethanol electrooxidation. We have demonstrated also that the electrochemically shape-controlled synthesis in DESs proves advantageous in controlling the size and shape of Pt NCs without the addition of seeds, surfactants, or other chemicals and could be applied in the synthesis of other noble metal NCs with high surface energy and high catalytic activity.