Pt-Cu and Pt-Pd-Cu concave nanocubes with high-index facets and superior electrocatalytic activity.

Pt-Cu nanostructures: Pt-Cu nanocubes (NCs), concave nanocubes (CNCs), and Pt-Pd-Cu CNCs with high-index facets (HIFs) were prepared through progressive galvanic replacements in a one-pot hydrothermal approach. The HIF-enclosed CNCs showed superior activities to (100)-enclosed NC catalysts for methanol oxidations owing to the modification of both the surface electronic structures and the surface atomic arrangements (see figure).