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.