Syntheses and evaluations of CdS with various morphologies for photocatalytically reducing CO₂

Abstract

A series of CdS with various shapes of microsphere, flower-like and leaf-like were templatefreely synthesized by a hydrothermal method. Powder X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM) and UV-vis absorption spectroscopy (UV-vis) were applied to characterize the morphology, optical and other physical properties of the as-prepared CdS. An optical spectrum analyzer was used to measure the wavelength of the illuminant on the slurry in the activity evaluations of photocatalytic reduction of CO₂ over CdS. Both sources of cadmium and sulfur had great impact on the CdS morphology as can be seen in the SEM images. By means of a series of activity evaluations, the microspheric CdS made from cadmium nitrate and thioacetamide showed better photocatalytic activity for the reduction of CO₂ to methyl formate (MF) in methanol than the flower-like and leaf-like CdS catalysts.

Keywords

CdS / morphology / photocatalytic reduction / CO₂ / methyl formate

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