Photodegradation of phenol red on a Ni-doped niobate/carbon composite
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Data
2014-08-01
Autores
Lanfredi, Silvania [UNESP]
Nobre, Marcos Augusto Lima [UNESP]
Moraes, Paula G. P. [UNESP]
Matos, Juan
Título da Revista
ISSN da Revista
Título de Volume
Editor
Elsevier B.V.
Resumo
The photocatalytic activity of a new nanostructured Ni-doped niobate KSr2(Ni0.75Nb4.25)O15-delta was studied using the phenol red dye as a test molecule and the influence of amorphous carbon deposits upon the photoactivity of the niobate-based materials was also verified. KSr2(Ni0.75Nb4.25)O15-delta powder was prepared by a high energy ball milling method and the C-KSr2(Ni0.75Nb4.25)O15-delta composite by the partial pyrolysis of the niobate dispersed in a polyester matrix. Materials were characterized by FM spectroscopy and X-ray diffraction (XRD). The diffraction line profile and the refinement of the structural parameters of KSr2(Ni0.75Nb4.25)O15-delta were derived by the Rietveld method. Both samples showed similar phenol red photodegradation under steady-state kinetic conditions. However, amorphous carbon seems to beneficially affect the reaction mechanism which followed first order kinetics. In terms of KSr2(Ni0.75Nb4.25)O15-delta concentration a clear enhancement in the photoactivity of the niobate in the presence of amorphous carbon by a factor 4.7 was found suggesting a synergy effect between both solids. We conclude that C-KSr2(Ni0.75Nb4.25)O15-delta composite can be employed for the photocatalytic degradation of diluted pollutants. (c) 2014 Elsevier Ltd and Techna Group S.r.l. All rights reserved.
Descrição
Palavras-chave
Amorphous carbon, Phenol red dye, Photocatalysis, TTB-type structure
Como citar
Ceramics International. Oxford: Elsevier Sci Ltd, v. 40, n. 7, p. 9525-9534, 2014.