Photocatalytic degradation of phenol derivatives over silver supported on mesoporous titania nanoparticles

In this study, the potential of silver supported on mesoporous titania nanoparticles (Ag-MTN) as visible-light-driven photocatalyst was investigated for the degradation of phenol derivatives. Characterisation results illustrated that the presence of Ag reduced the band gap of MTN and increased the number of oxygen vacancies (OV) and Ti3+ site defect (TSD). The presence of both properties is among the important factors that need to be considered for catalyst properties in order to achieve effective photocatalytic degradation under visible light. The photoactivity of the catalyst was also significantly influenced by the presence of Ag, which acted as an electron trap that enhanced electron-hole separation. The ability of Ag-MTN to degrade phenol derivatives [phenol (Ph), 2-chlorophenol (2-CP), 2,4-dichlorophenol (2,4-diCP), and 4-acetamidophenol (4-AcePh)] was compared with commercial TiO2 and MTN. The percentage degradation of phenol derivatives was in the following order: TiO2 < MTN < Ag-MTN. This indicated that the presence of Ag in MTN effectively enhanced the photoactivity of MTN towards the degradation of phenol derivatives