Surface ligand-mediated isolated growth of Pt on Pd nanocubes for enhanced hydrogen evolution activity

Br ⁻ ions can affect the growth mode of Pt on a Pd substrate. When Br ⁻ ions adsorb on some sites of the Pd cube, the newly formed Pt atoms tended to grow on the Br ⁻ free area, facilitating island growth mode. Otherwise, without Br ⁻ ions, because of the relatively high diffusion rate between Pt and Pd, Pt atoms can epitaxially deposit on the whole surface of the Pd nanocubes, forming a layered growth mode structure.