Synthesis of vacancy-rich titania particles suitable for the additive manufacturing of ceramics
Jaime Benavides, Luis Felipe Gerlein, Charles Trudeau, Debika Banerjee, Xiaohang Guo, Sylvain G. Cloutier
Abstract
Abstract In the last decades, titania (or TiO 2 ) particles played a crucial role in the development of photo-catalysis and better environmentally-friendly energy-harvesting techniques. In this work, we engineer a new generation of TiO 2 particles rich in oxygen vacancies using a modified sol–gel synthesis. By design, these vacancy-rich particles efficiently absorb visible light to allow carefully-controlled light-induced conversion to the anatase or rutile crystalline phases. FTIR and micro-Raman spectroscopy reveal the formation of oxygen vacancies during conversion and explain this unique laser-assisted crystallization mechanism. We achieve low-energy laser-assisted crystallization in ambient environment using a modified filament 3D printer equipped with a low-power laser printhead. Since the established high-temperature treatment necessary to convert to crystalline TiO 2 is ill-suited to additive manufacturing platforms, this work removes a major fundamental hurdle and opens whole new vistas of possibilities towards the additive manufacturing of ceramics, including carefully-engineered crystalline TiO 2 substrates with potential applications for new and better photo-catalysis, fuel cells and energy-harvesting technologies.