Solvent effects on properties of metallo-organic derived Ni/NiO thin films

Ni/NiO thin films for potential uses in batteries, fuel cells, sensors and supercapacitors were prepared by metallo-organic decomposition technique, using a unique solvent system of propionic acid (PPA) and amylamine (AA), in 0.5–2.0 molar ratios and 1 M Ni acetate precursor solute. This mixed solvent system exhibits ionic molecular clusters in solution, with nickel ions forming square planar coordinate complexes with the carboxylate groups, leading to easy film formation on spin coating at 3000 rpm and densification below 350 °C. Nano-sized (~ 50 nm), high surface area, low resistive (~ 600 nΩ m) Ni/NiO thin films were developed at a molar ratio of 1:1 AA/PPA using this methodology.