Effect of Iron, Titanium, Vanadium, and Indium Oxides on the Width of the Band Gap and Photoluminescence Intensity of Mesoporous Tin Oxide

A study was carried out on the effect of iron, titanium, vanadium, and indium oxides in mesoporous tin dioxide (obtained using the nonionic surfactant Pluronic F127 as the template in ethanolic media) on the band gap and photoluminescence intensity. The UV absorption maximum is shifted toward shorter wavelengths upon the introduction of low concentrations of iron and titanium oxides, while there is a shift toward longer wavelengths upon the introduction of more than 10 mole % vanadium and indium oxides. The introduction of oxides does not lead to the appearance of new visible bands of significant intensity in the range 350-550 nm but only alters the photoluminescence intensity due to electronic transitions in the valence band from electron donor (“defective”) levels located in the band gap.