Solar-light driven photocatalytic conversion of p-nitrophenol to p-aminophenol on CdS nanosheets and nanorods.

A simple synthetic protocol devoid of toxic surfactants was applied for the synthesis of CdS nanosheets and nanorods by thermolyzing bis (4-benzylpiperadine-1-carbodithioate-κ 2 S, S′) cadmium(II) ( 1 ) and propane-1,3-diyl bis (piperidincarbamodithioate)cadmium(II) ( 2 ) using ethylenediamine (en) as a solvent. The as obtained products were characterized by TEM, PXRD, and UV–Visible spectroscopy. The nanosheets ( 1) and nanorods ( 2) were confirmed by HR-TEM with a lattice spacing of 0.33 nm which corresponds to the 002 plane of hexagonal CdS, observations in consonance with XRD. Based upon the band gap obtained from UV–Vis, 2.91 eV (nanosheets) and 2.65 eV (nanorods), these nanoparticles (NPs) were used as solar light driven photocatalyst for the conversion of p -nitrophenol to p- aminophenol. The nanorods (8 min) were found slightly more efficient than nanosheets (10 min), and the conversion efficiency of both remained above 92% even after 3rd cycle without any structural damage as revealed by the afterward PXRD. The better catalytic activity of both morphologies can be attributed to quantum size effect and good optical absorbance. [ABSTRACT FROM AUTHOR]