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Microwave synthesis and photocatalytic activity of nano lanthanide (Ce, Pr, and Nd) orthovanadates / Sudarshan Mahapatra in Industrial & engineering chemistry research, Vol. 47 N°17 (Septembre 2008) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 47 N°17 (Septembre 2008) . - p. 6509–6516 Titre : Microwave synthesis and photocatalytic activity of nano lanthanide (Ce, Pr, and Nd) orthovanadates Type de document : texte imprimé Auteurs : Sudarshan Mahapatra, Auteur ; Susanta K. Nayak, Auteur ; Giridhar Madras, Auteur Année de publication : 2008 Article en page(s) : p. 6509–6516 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Lanthanide  orthovanadates  Photocatalytic  activities  Crystal  structure  X-ray  diffraction Résumé : Lanthanide orthovanadates, CeVO4, PrVO4, and NdVO4, of nanodimensions were synthesized under microwave exposure, and the photocatalytic activities of these compounds were investigated. These compounds exhibit a tetragonal zircon structure, crystallizing in the space group I41/amd with a = 7.3733(4) and c = 6.4909(4) Å with Z = 4. The crystal structure was analyzed by powder X-ray diffraction, and the band gap was analyzed by UV−visible spectroscopy. Particle sizes were in the range of 25−30 nm, as observed by transmission electron microscopy. While the energy dispersive X-ray analysis indicates the formation of LnVO4, thermal analysis of these solids shows stability of the phase up to 1000 °C. The photocatalytic activity of all these orthovanadates has been investigated by degrading various dyes like methylene blue (MB), Orange G (OG), Rhodamine B (RB), Rhodamine Blue (RBL), and Remazol brilliant blue (RBBR) under UV irradiation. Further, these compounds were also used to degrade organic pollutants like phenol, 2,4-dinitrophenol and 2,4-dichlorophenol. The degradation rates of dyes and organics in presence of microwave-synthesized orthovanadates are higher compared to that observed with orthovanadates synthesized by the solid state technique. The microwave-synthesized orthovandates also show chloro-specificity, with the rate of degradation of 2,4-dichlorophenol significantly higher than that observed in presence of Degussa P-25 titania. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie8003094 [article] Microwave synthesis and photocatalytic activity of nano lanthanide (Ce, Pr, and Nd) orthovanadates [texte imprimé] / Sudarshan Mahapatra, Auteur ; Susanta K. Nayak, Auteur ; Giridhar Madras, Auteur . - 2008 . - p. 6509–6516. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 47 N°17 (Septembre 2008) . - p. 6509–6516 Mots-clés : Lanthanide  orthovanadates  Photocatalytic  activities  Crystal  structure  X-ray  diffraction Résumé : Lanthanide orthovanadates, CeVO4, PrVO4, and NdVO4, of nanodimensions were synthesized under microwave exposure, and the photocatalytic activities of these compounds were investigated. These compounds exhibit a tetragonal zircon structure, crystallizing in the space group I41/amd with a = 7.3733(4) and c = 6.4909(4) Å with Z = 4. The crystal structure was analyzed by powder X-ray diffraction, and the band gap was analyzed by UV−visible spectroscopy. Particle sizes were in the range of 25−30 nm, as observed by transmission electron microscopy. While the energy dispersive X-ray analysis indicates the formation of LnVO4, thermal analysis of these solids shows stability of the phase up to 1000 °C. The photocatalytic activity of all these orthovanadates has been investigated by degrading various dyes like methylene blue (MB), Orange G (OG), Rhodamine B (RB), Rhodamine Blue (RBL), and Remazol brilliant blue (RBBR) under UV irradiation. Further, these compounds were also used to degrade organic pollutants like phenol, 2,4-dinitrophenol and 2,4-dichlorophenol. The degradation rates of dyes and organics in presence of microwave-synthesized orthovanadates are higher compared to that observed with orthovanadates synthesized by the solid state technique. The microwave-synthesized orthovandates also show chloro-specificity, with the rate of degradation of 2,4-dichlorophenol significantly higher than that observed in presence of Degussa P-25 titania. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie8003094