Coating Colloidal Carbon Spheres with CdS Nanoparticles: Microwave-Assisted Synthesis and Enhanced Photocatalytic Activity

• Published in: Langmuir 2010-12, Vol.26 (23), p.18570-18575
• Main Authors: Hu, Yong, Liu, Yu, Qian, Haisheng, Li, Zhengquan, Chen, Jiafu
• Format: Article
• Language: English
• Subjects: Cadmium - chemistry; Cadmium Compounds - chemistry; Carbon - chemistry; Catalysis; Chemistry; Chemistry - methods; Colloidal state and disperse state; Colloids - chemistry; Devices and Applications: Sensors, Fluidics, Patterning, Catalysis, Photonic Crystals; Exact sciences and technology; General and physical chemistry; Ions; Metal Nanoparticles - chemistry; Microscopy, Electron, Transmission - methods; Microwaves; Nanoparticles - chemistry; Nanospheres - chemistry; Photochemistry; Photochemistry - methods; Physical and chemical studies. Granulometry. Electrokinetic phenomena; Physical chemistry of induced reactions (with radiations, particles and ultrasonics); Sulfides - chemistry; X-Ray Diffraction
• ISSN: 0743-7463; 1520-5827
• DOI: 10.1021/la103191y

This manuscript describes the accurate coating of CdS nanoparticles on the surface of colloidal carbon spheres by a facile two-step, microwave-assisted method and the studies on the photocatalytic activity of the C@CdS core−shell spheres. For the coating of CdS nanoparticles, cadmium ions were incorporated into the hydrophilic shell of colloidal carbon spheres and reacted with an introduced sulfur source under a microwave field to obtain the C@CdS hybrid spheres. Using this process, the as-prepared hybrid structures preserved the good dispersity and uniformity of initial carbon spheres, and the thickness of the CdS nanoparticles shell could be varied or controlled by the irradiation time. A photoluminescence spectrum showed that the C@CdS hybrid spheres feature a broad green emission at around 494 nm (λex = 337 nm). Additionally, CdS nanospheres were successfully prepared in aqueous solution via a microwave-assisted route, and the effect of irradiation time on the products was also investigated. The studies of the photocatalytic property demonstrate that these fabricated functional hybrid structures evinced a higher photocatalytic degradation activity when exposed to visible light irradiation than that of CdS nanospheres under the same conditions.