Efficient porous carbon/CdS composite photocatalyst for dye degradation

This very paper focuses on the preparation of an eco-friendly and efficient photocatalyst aiming to degrade organic dyes in wastewater. The cheap and abundant straws were carbonized to prepare porous carbon pieces in this study. A simple hydrothermal method was employed to prepare the porous carbon/CdS (PC/CdS) composite. CdS nanoparticles were anchored on these porous carbon sheets, forming the PC/CdS composite. The composite was annealed at 300, 400, and 600 °C, respectively, and then these samples were characterized by SEM, TEM, XRD, and FTIR. As an important parameter, the porosities of PC and the PC/CdS were characterized by BET method. Particularly, the photo-electronic response of PC/CdS has been characterized by EIS, PL, and transient photocurrent. It is found that the carrier mobility and shape of PC itself and the annealing process improved the photocatalytic activity, as well as adsorption ability. Those composites were able to thoroughly degrade RhB within 90 min under the irradiation of visible light. What is interesting and quite different from other reports is that there was no conjugated part of RhB left in the solution after photocatalytic degradation.