Bimetallic nanocrystals bound by high-index facets are promising catalysts, as they have both electronic effects from alloying and surface structure effects from high-index facets. Herein, we mainly focused on electrochemical preparation of two new Pt-Rh nanocrystals with high-index facets: {830}-bound tetrahexahedron and {311}-bound trapezohedron, and their excellent electrocatalytic properties for ethanol oxidation, especially the ability to break C-C bonds. Combining previous results about surface-modified tetrahexahedral Pt nanocrystals, we discuss the correlation of alloy and surface effects of the bimetallic system.