Tellurium-Doping Mediated Synthesis of Edge- and Corner-Truncated Gold Octahedra and Their Plasmonic and Electrocatalytic Properties

Controlling nanocrystal morphology through facet-specific capping agents enables the precise engineering of noble metal nanostructures. Here, we demonstrate that tellurium (Te) doping directs the growth of Au nanocrystals by stabilizing surface facets. By modifying Au seed surfaces with Te species, we achieve a morphological transformation from cuboctahedral seeds to uniquely edge- and corner-truncated octahedra─a structure unattainable without Te mediation. Density functional theory (DFT) simulations reveal that Te incorporation increases the vacancy formation energy of Au facets and realizes p–p orbital overlapping, enhancing their thermodynamic stability. UV–vis spectroscopy and finite-difference time-domain simulations confirm that Te doping has a minimal impact on plasmonic properties, preserving the optical characteristics of Au. The carbon-supported Au₈Te₁ ECTOs demonstrate exceptional electrocatalytic performance, achieving a remarkable specific activity of 10.5 mA cm^–2, a 36-fold enhancement over conventional Au nanoparticles (0.29 mA cm^–2), simultaneously exhibiting accelerated reaction kinetics and outstanding long-term operational stability. DFT calculations reveal that Te incorporation stabilizes high-energy Au facets and boosts the catalytic performance. This work establishes Te doping as a powerful strategy for designing nonmetal-doped noble metal nanocrystals with tailored facet architectures, offering opportunities for optical and electrocatalytic applications.