Photo degradation of synthetic dyes using cadmium sulfide nanoparticles synthesized in the presence of different capping agents

• Published in: Separation and purification technology 2012-03, Vol.88, p.39-45
• Main Authors: Upadhyay, Ravi Kant, Sharma, Meenakshi, Singh, Deepesh Kumar, Amritphale, S.S., Chandra, Navin
• Format: Article
• Language: English
• Subjects: acetic acid; Applied sciences; cadmium; Capping agents; Catalysis; Catalytic reactions; CdS nanoparticles; Chemical engineering; Chemistry; crystallites; dyes; EDTA (chelating agent); ethylene; Exact sciences and technology; General and physical chemistry; nanoparticles; Photo-catalyst; photolysis; potassium; Reactors; surface area; Synthetic dyes’ photo-degradation; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; thermogravimetry; transmission electron microscopy; Water color removal; X-ray diffraction
• ISSN: 1383-5866; 1873-3794
• DOI: 10.1016/j.seppur.2011.11.040

Photo-degradation of synthetic dyes, namely crystal violet and methylene blue by cadmium sulfide nanoparticles synthesized by micro-emulsion/arrested precipitation routes, using three different capping agents, has been investigated. The synthesized cadmium sulfide nano particles are observed to be a mixture of cubic and hexagonal phases and have a crystallite size and surface area of 3.7, 6.8 and 13.9nm and 32.11, 29.54 and 8.63m2/g, respectively, when thioglycolic acid, potassium pyrosulfate and disodium salt of ethylene diamine tetra acetic acid (EDTA) are used as capping agent. HRTEM images of CdS nanoparticles synthesized using different capping agents (A) CdS-T, (B) CdS-K and (C) CdS-E. Pictures showing photo degradation of (D) crystal violet and (E) methylene blue dyes for different periods of exposure (in min) using thioglycolic acid capped CdS nanoparticles. [Display omitted] ► First time potassium pyrosulfate is used as capping agent for making nano particles. ► Performance of three capping agents for photocatalytic efficiency of CdS is compared. ► Synthesis protocol may be amenable for up gradation (although not tried in this paper). Photo-degradation of synthetic dyes by cadmium sulfide nano-particles synthesized by micro-emulsion/arrested precipitation routes using thioglycolic acid; potassium pyrosulfate and disodium salt of ethylene diamine tetra acetic acid (EDTA) as capping agents have been investigated. Synthesized nanoparticles have been characterized by X-ray diffraction, thermo-gravimetric analysis, high-resolution transmission electron microscopy, BET surface area analysis and UV–Vis spectro-photometry. The synthesized cadmium sulfide nano particles are observed to be a mixture of cubic and hexagonal phases and have crystallite size and surface area of 3.7, 6.8 and 13.9nm and 32.11, 29.54 and 8.63m2/g for thioglycolic acid, potassium pyrosulfate and EDTA capping agents, respectively. As expected, the photo-catalytic efficiency of nano-particles for degradation of dyes is observed to increase with increase in surface area (decrease in particulate size).