Geopolymer-TiO2 Nanocomposites for Photocsatalysis: Synthesis by One-Step Adding Treatment Versus Two-Step Acidification Calcination

Geopolymer-TiO2 nanocomposites were prepared by two different techniques, namely the two-step acidification calcination treatment and one-step adding method. The potential photocatalytic activities of geopolymer-TiO2 nanocomposites prepared by the two different methods were tested and compared. Nanocomposites prepared via the one-step process showed better photocatalytic activity. The amount of TiO2 particles loaded on the surface of the foaming materials was investigated by XRD and SEM-Mapping. By comparing with the sample obtained from two-step treatment, the TiO2 particles were distributed uniformly on the surface of the foaming materials for the sample obtained from the one-step method in this study. Results showed that the specific surface area of the geopolymer-TiO2 prepared by the one-step treatment process (28.67 m2/g) was significantly lower than the two-step acidification calcination process (215.04 m2/g), while the photocatalytic efficiency with methylene blue trihydrate (MB) was better. This is due to the more stable structure of geopolymer-TiO2 nanocomposites, the better dispersion and more loading of TiO2 particles on the foaming materials surfaces, leading to the enhanced photocatalytic activity. View Full-Tex