Preparation of carbon-supported CdS photocatalysts with high performance of dye photodegradation using cadmium-enriched Perilla frutescens biomass

Cadmium sulfide (CdS), which is a typical and important semiconductor, has become enormous research concern in photocatalysis for environmental remediation. However, the practical usage of CdS in photocatalysis was largely limited because of photocorrosion, and the toxic Cd2+ ions would be released which leading to the potential environmental risks. To improve this defect, specific research has been focusing on fabrication of stable CdS nanocomposites by supporting with carbon-based materials. In this study, cadmium-enriched Perilla frutescens root was selected to in situ fabricate carbon-supported CdS nanocomposite photocatalyst. It was found that the CdS@CP contained CdS nanoparticles which were indexed to mixed-phase cubic and hexagonal CdS. Estimated band gap energy of CdS@CP (2.21 eV) was obviously lower than the pure CdS (2.57 eV), which implying that the new synthesis of CdS@CP was more easily to be motivated by visible light and required less energy compared with pure CdS. Moreover, the photodegradation rate of Rhodamine B (RhB) by CdS@CP was ca. 98%, and it exhibited high catalytic performance and durability in photodegradation of dye. The synthesis of CdS@CP photocatalysts with high performance of dye photodegradation would be a facile and low-cost pathway for achieving high value utilization of Cd-enrich biomass.