Metal deposits, compositions, and methods for making the same

A method of forming a metal deposit on a substrate, the method comprising:

• forming a metal deposit on a substrate from an electrolyte composition, the electrolyte composition comprising a carboxamide, a trialkylamine hydrochloride, and a metal salt;
• the metal deposit being formed on the substrate by inducing a potential between the metal salt and the substrate through the electrolyte composition to cause a metal-metal bond to form between the metal salt and the substrate;
• the carboxamide comprising Formula (I):
• wherein n is 1 to 6;
• each Q is O;
• R1 is independently chosen from H or alkyl, and R3 is NR4R5;
• or R1 and R3 are taken together to form a ring;
• and
• each R2, R4, and R5 is independently chosen from H or alkyl;
• the trialkylamine hydrochloride being selected from the group consisting of trimethylamine hydrochloride (TMA-HCl), triethylamine hydrochloride (TEA-HCl), triethanolamine hydrochloride, and combinations thereof;
• and
• the metal salt having a formula MXy, wherein M is a metal, X is a halide, and y is an oxidation number of M;
• wherein the trialkylamine hydrochloride and the carboxamide are present in the electrolyte composition in molar ratio between 1:3 and 1:30 to form an ionic liquid, and the metal salt is present in the electrolyte composition in a concentration between 0.2 and 1.5 moles per liter of the ionic liquid;
• and
• wherein the metal deposit is formed on the substrate from the electrolyte composition such that the metal deposit has an average grain size between 0.2 μm and 3 μm and contains less than 1 mol % of each oxygen, carbon, and chlorine.