An unexpected, self-regulating codeposition of nickel and platinum forming deposits with surfaces enriched in platinum

Galvanostatic depositions onto Ni substrates from 0.2 M NiCl2 in 2.0 M NH4Cl using a Pt counter electrode are self-regulating, forming rough Pt-Ni deposits with ∼1.8 mol% Pt. All or most of the Pt is on the surface of these deposits. Use of added H2PtCl6·6H2O as a source of Pt(IV), or K[PtCl3(C2H4)]·H2O as a source of Pt(II), results in Pt-Ni deposits with the Pt dispersed throughout the deposit, with little Pt on the surface. Ni promotes the electrooxidation of 2-propanol over Pt in alkaline electrolytes.