Synthesis of nickel sulfide by homogeneous precipitation from acidic solutions of thioacetamide

Nickel sulfide powders were precipitated by utilizing the thermal decomposition of thioacetamide in acidic aqueous solutions. Precipitation was induced by a direct reaction between thioacetamide and nickel at 70 degrees and 80 degrees C with thioacetamide concentrations of 0.80M. Precipitation was induced by reaction of sulfide ions with nickel at 90 degrees C and at low pH. Direct reaction products were amorphous and contained significant amounts of carbon, excess sulfur, and hydrogen. Hydrolysis-controlled precipitation yielded faceted crystalline particles 2 to 4 mu m in size. Crystalline, spherical particles with compositions near stoichiometric NiS were precipitated with high yields.