Bandgap optimization of sol–gel-derived TiO <sub>2</sub> and its effect on the photodegradation of formic acid
Morad Zouheir, Ouissal Assila, Karim Tanji, Abdelali El Gaidoumi, J. Araña, J.M. Doña-Rodrı́guez, Jan‐Henrik Smått, Tan‐Phat Huynh, Abdelhak Kherbeche
Abstract
Abstract This work reports a key factor, the H 2 SO 4 concentration, in controlling the physicochemical properties of titanium dioxide (TiO 2 ) photocatalysts during the sol–gel synthesis. The photocatalysts synthesized using different concentrations of H 2 SO 4 possess specific anatase/rutile ratios and crystallite sizes as well as surface areas, resulting in different photocatalytic performance in the degradation of formic acid in solution. The best photocatalytic performance is observed for the TiO 2 photocatalyst containing a relatively high percentage of the rutile phase (∼84%), which is obtained from the sol–gel synthesis without H 2 SO 4 .