TiO2 Modified Geopolymers for the Photocatalytic Dye Decomposition

This article studies the photocatalytic activity of three types of industrially produced TiO2 powder (P25, CG100 and CG300) incorporated into a parent geopolymer matrix, and their pure counterparts, based on the decomposition of Rhodamine B dye. Rhodamine B dye is applied as a model substance because it is frequently used in the textile industry and thus may be present in the wastewater. The average particle size, specific surface area and mineralogical composition of TiO2 powders have been determined. The geopolymer matrix works well as a supporting material for the CG100 and P25 pure types of TiO2 powder as these input materials have better properties such as a higher average particle size, lower specific surface area, mineralogicalcomposition, etc., than the CG300 TiO2 powder. These properties (or their combination) affect the photocatalytic activity of the resulting materials, which may thus become advanced composites with an additional purifying ability, e.g., materials that can be used for wastewater treatment or air purification.