New nanostructured CdS fibers for the photocatalytic reduction of 4-nitrophenol

The photocatalytic activity of new nanostructures of CdS (nanofiber) was investigated in the 4-nitrophenol reduction under either visible or UV light irradiation, using Na2SO3 as reducing agent. The nanostructures of CdS were synthesized by precipitation method in an ethylenediamine–water solution at moderate conditions (low temperatures and short aging time) and their structural, optical and morphological properties were characterized by X-ray diffraction, UV–vis spectroscopy and transmission electron microscopy. The new CdS nanofiber with quantum confinement effect presented the highest photo-efficiency for the photoreduction of 4-nitrophenol under visible light irradiation; however when the quantum confinement effect was extremely strong their maximum photoactivity was only observed under UV light irradiation.