Surface and Near-Surface Engineering of PtCo Nanowires at Atomic Scale for Enhanced Electrochemical Sensing and Catalysis

Among the most efficient strategies to boost the electrochemical sensing and catalysis of Pt-based multimetallic nanomaterials is atomically manipulating the surface and near-surface nanostructures, which directly govern the adsorption behavior. Using one-dimensional PtCo urchin-like nanowires as the platform, we herein achieve the construction of high-index faceted Pt-skin configuration. Such unique structure shows excellent electrocatalytic performance toward the electrochemical detection of various molecules (H2O2, NH2NH2, dopamine, and acetaminophen), with the capability of real-time monitoring of H2O2 released from living cells and an impressive detection limit of 0.4 nM. Meanwhile, the combination of high-index facet and Pt-skin architecture also enables enhanced catalytic activity for the electro-reduction of oxygen in acid, realizing a very high mass activity of 2.2 A/mgPt. Our study demonstrates the great potential of surface and near-surface engineering at the atomic level in promoting the electrocatalysis on multimetallic nanomaterials for electrochemical sensors and renewable energy technologies