Optimization of Opto-Electrical and Photocatalytic Properties of SnO2 Thin Films Using Zn2+ and W6+ Dopant Ions

Abstract

A series of Zn 2? and W 6? doped tin oxide (SnO 2 ) thin films with various dopant concentrations were prepared by spray pyrolysis deposition, and were characterized by X-ray diffraction, atomic force microscopy, contact angle, absorbance, current density-voltage (J-V) and photocurrent measurements. The results showed that W 6? doping can prevent the growth of nanosized SnO 2 crystallites. When Zn 2? ions were used, the crystallite sizes were proved to be similar with the undoped sample due to the similar ionic radius between Zn 2? and Sn 4? . Regardless of the dopant ions' type or concentration, the surface energy has a predominant dispersive component. By using Zn 2? dopant ions it is possible to decrease the band gap value (3.35 eV) and to increase the electrical conductivity. Photocatalytic experiments with methylene blue demonstrated that with zinc doped SnO 2 films photodegradation efficiencies close to 30% can be reached.

Volatile Organic Compounds (VOCs) Removal from Indoor Air by Heterostructures/Composites/Doped Photocatalysts: A Mini-Review

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The Influence of Photoactive Heterostructures on the Photocatalytic Removal of Dyes and Pharmaceutical Active Compounds: A Mini-Review

“…As presented in Figure 1 , during the photocatalytic degradation of organic pollutants, the photogenerated electrons and holes are trapped by dissolved O 2 and H 2 O [ 39 , 40 ]. Highly reactive oxygen species, including superoxide (O 2 – ) and hydroxyl radicals (OH), are developed under light irradiation [ 41 , 42 ].…”

Tuning the opto-electrical properties of SnO2 thin films by Ag+1 and In+3 co-doping

“…The current-voltage and photocurrent measurements were performed using a multichannel potentiostat (PAR Instruments, model HM 8143) with frequency analyzer, a monochromator (Acton, SpectraPro 2150i) and a UV-vis light source (Oriel, model 7123). The current-voltage analyses were previously detailed [35]. Transmittance spectra were recorded using a UV-vis spectro-photometer (Perkin-Elmer Lambda 950 UV-vis-NIR) with integrating sphere, in the spectral range 350-1400 nm, with a scan rate of 60 nm/min (lamp changes at 326 nm).…”