Preparation of titanium monoxide nanopowder by low-energy wet ball-milling

•TiO nanopowder was synthesized by milling commercial TiO micron-sized powder.•A green and simple method to synthesize TiO nanopowder is presented.•Cubic TiO was obtained from monoclinic TiO by annealing under vacuum.•Annealed TiO has low electrical resistivity and preserves its optical property.•Milled TiO with smallest particle size shows the best dispersibility.

Titanium monoxide (TiO), which is a versatile ceramic material with a low electrical resistivity and an extreme hardness, has received considerable attention for potential applications in decorative and protective coatings, and in microelectronic layered structures. In this study, a green and simple method to synthesize titanium monoxide (TiO) nanoparticles from commercial TiO micro sized powder through low-energy wet ball-milling is presented. The as-milled TiO powder shows good dispersibility in ethylene glycol, indicating a promising material for solution-based production. During annealing in a vacuum at 900 °C, the as-milled TiO powder transforms from monoclinic to cubic structure. The annealed TiO, in the form of a pellet, shows a very low electrical resistivity (2.1 mΩ cm). When dispersed in ethylene glycol, the annealed TiO powder almost preserves the optical property of the as-milled TiO by presenting a gradual increase in absorption from visible range to near-infrared region. Thus, low-energy wet ball-milling is an environmentally friendly and effective method to synthesize TiO nanopowder for a variety of purposes.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slide