Photocatalytic reduction of aromatic nitro compounds using CdS nanostructure under blue LED irradiation

The aromatic nitro compounds reduced with a high selectivity to the corresponding amines under blue LED irradiation (3 W) using CdS nanostructure as photocatalyst. The reaction is relatively sensitive to the electron demands of the substituents. The nitro compounds with electron withdrawing groups (CN, COR, NO2) give higher yields than with the electron donating groups (OMe, Me). In the nitro compounds with low activity, the high yields of corresponding amines were achieved by the addition of ammonium format. The CdS nanostructure showed excellent photocatalytic performance for the reduction of nitrobenzene compared with commercial CdS (Aldrich) under visible LED irradiation. The results demonstrated that CdS nanostructure have potential to provide a promising visible light driven photocatalyst for the selective reduction of nitro compounds to corresponding amines under mild conditions. The excellent reusability of the photocatalyst was examined for six runs.