The photoreactivity of TSP, a microporous titanosilicate with the pharmacosiderite structure consisting of nanoclusters of titania octahedra linked through silicate tetrahedra, has been studied by EPR spectroscopy. UV irradiation of TSP in the presence of O-2 produces the EPR signal of holes trapped at. oxide ion sites (O-). This is attributed to the scavenging of electrons by O-2. The trapped holes in TSP are much more stable than the corresponding species in TiO2. Reaction of O-2 with O- to form O-3(-) is also observed. Trapped holes can be seen as well when TSP is irradiated in the presence of adsorbed CO2, which can also act as an electron scavenger.
|Number of pages||7|
|Journal||Microporous and Mesoporous Materials|
|Early online date||5 Dec 2006|
|Publication status||Published - 19 Apr 2007|
- hole trapping
- electron trapping
- anatase TIO2 particles