Rashad et al. (2013) reported that heterogeneous photocatalysis using semiconductor has been found to be highly effective
for environmental application. In this contribution, ZnO doped SnO2 (Is this right?) has been successfully synthesized.
The prepared photocatalysts were tested by the determination of photocatalytic degradation of methylene blue (MB). The
results indicated that Zn2+ doping at 0.3 ZnO: 0.7 SnO2 molar ratio showed the highest MB photodegradation. The ZnO/
SnO2 photocatalysts were quite stable since no decrease in activity in the first four cycles was observed. Design of catalyst
material should also be useful in photocatalysis, with the capability of destruction of pollutants and carrying out selective
catalytic processes. Microwave-assisted photocatalytic degradation of dyes is one of the emerging technologies for waste
water remediation. Microwave effectively accelerates photocatalytic degradation, when microwave electrodeless lamp(MEL)
substitutes traditional UV lamp as light source. This setup can be extremely simplified if MEL and photocatalyst
can be replaced by a catalyst which can work under microwave irradiation in the absence of any light source. The work is
reporting for the first time degradation of acid orange 7(AO) under microwave irradiation using polyaniline (PANI)
as catalyst in the absence of any UV lamp as light source (Riazet al., 2013). The degradation/decolorization was carried out in
neutral acidic and basic media and was monitored spectrophotometrically to evaluate the ability of microwave irradiation to
degrade AO. Microwave irradiation showed excellent performance as it completely decolorizes AO dye solution in10 min. With
the advantages of low cost and rapid processing,this novel catalyst is expected to gain promising application in the treatment of
various dyestuff wastewaters on a large scale.