Eur. Phys. J. Appl. Phys. 96, 20901 (2021)
https://doi.org/10.1051/epjap/2021210144

Regular Article

Low-cost thermo-chemical process of TiO₂ powder purification: study of iterative gettering effect

¹ Laboratoire de photovoltaïque (LPV), Centre de Recherches et des Technologies de l'Energie (CRTEn) BorjCedria B.P N°952050-Hammam Lif, Tunisia
² Faculty of Mathematical, Physical and Natural Sciences of Tunis, University of Tunis El Manar, Tunisia

^* e-mail: khalifa_marouan@yahoo.fr

Received: 30 June 2021
Received in final form: 18 September 2021
Accepted: 14 October 2021
Published online: 15 November 2021

Abstract

The titanium dioxide (TiO₂) purity is very important for the TiO₂-based applications making essential the impurities density reduction. In this study, we propose an efficient purification process of TiO₂ powder in order to reduce impurities. The low-cost proposed approach is based on an iterative gettering (IG) process combining three main steps: (1) a porous TiO₂ sacrificial layer formation (p-TiO₂), (2) a rapid thermal annealing (RTA) of p-TiO₂ powder in an infrared oven at 950 °C under air permitting the residual impurities diffusion to the porous layer surface and (3) etching in acid solution to remove the porous layer. Effect of the proposed gettering process on purification efficiency was evaluated by different characterization techniques such as the transmission electron microscopy (TEM), the energy dispersive X-ray spectroscopy (EDX), the UV–Visible-NIR spectroscopy, the X-ray diffraction (XRD) and atomic absorption spectroscopy (AAS). The obtained results showed the efficient removal of metal impurities, such as Cu, Al, P, and Fe confirming the efficiency of the process improving the purity from 89% to 99.96%.