Photocatalytic Reduction of Nitrobenzene with NaBH4 in Aqueous Medium Over the Ag/AgBr/TiO2/NZ and Ag/AgBr/NZ Nanocomposites

A new approach forward to photocatalytic reduction of nitro compounds was studied, over the clinoptilolate-based silver bromide and silver bromide-titanium dioxide photocatalysts that were prepared and characterized. The photoreaction performed at the presence of NaBH4 which is a strong reducing agent in solution medium. A new mechanism is proposed for nitrobenzene reduction under the photocatalytic conditions. The effect of pH, illumination source, NaBH4 concentration and temperature were also studied. The results showed that the best efficiency obtains over the Ag/AgBr/TiO2/NZ in natural pH under UV light. Also, we observed that the photoreduction efficiency was affected by changing the NaBH4 concentration and temperature. However the effect of former case was more considerable compared to the latter case.