The preparation and performance of Au loads TiO2 nanomaterials

Abstract

In this experiment, gold loaded TiO2 nanoparticles (AuNPS@TiO2NPS) and nanowires (AuNPS@TiO2NWS) were successfully prepared through one step hydrothermal reaction. The photocatalytic experimental results showed that the catalytic efficiency of Au loaded TiO2 increases with the increase of Au ratio. When the gold content was 5%, both AuNPS@TiO2NPS and AuNPS@TiO2NWS performed well in catalysis Methylene blue. It was also clear that AuNPS@TiO2NWS performed better than that of AuNPS@TiO2NPS. After calcination at 800 °C for 3 h under the protection of Ar, the crystal phase of both samples shifted to rutile. Furthermore, from SEM and TEM image, the linear structure was destroyed under high temperature which decreased the catalytic efficiency. It indicated that the crystal phase was strengthened and the catalytic effect was improved obviously by calcinations. By comparing the catalytic efficiencies of dyes with different initial concentrations after 5 h under UV irradiation, the time and content at which the AuNPS@TiO2NPS and AuNPS@TiO2NWS reached degradation saturation were related to the potential of catalyst surface. After five times of repeated use, the degradation rate could still be 87.25% for Methylene blue, 81.65% for Rhodamine B and 79.70% for Azophloxine. The results would indicate that the samples as prepared had good recycling performance.