Enhanced UV and visible light photocatalytic properties of synthesized AgBr/SnO2 composites

Composites (AgBr/SnO<inf>2</inf>) comprised of AgBr and SnO<inf>2</inf> with different molar % of bare SnO<inf>2</inf>, have been synthesized by simple precipitation methods; the bare SnO<inf>2</inf> used, was synthesized by hydrothermal procedure. Sam...

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Detalhes bibliográficos
Autores: Puga, F., Navío, José Antonio, Hidalgo, M. C.
Formato: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2021
País:España
Recursos:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/400369
Acesso em linha:http://hdl.handle.net/10261/400369
https://api.elsevier.com/content/abstract/scopus_id/85094607836
Access Level:acceso abierto
Palavra-chave:Dyes
AgBr
Caffeic acid
Photocatalysis
Tin oxide
Descrição
Resumo:Composites (AgBr/SnO<inf>2</inf>) comprised of AgBr and SnO<inf>2</inf> with different molar % of bare SnO<inf>2</inf>, have been synthesized by simple precipitation methods; the bare SnO<inf>2</inf> used, was synthesized by hydrothermal procedure. Samples have been characterized by X-ray diffraction (XRD), N<inf>2</inf>-adsorption, UV–vis diffuse reflectance spectroscopy (DRS), scanning electron microscopy (SEM), Transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). Photocatalytic activity of the as-prepared photocatalysts was evaluated through photocatalytic degradation of rhodamine B (RhB) and caffeic acid (CAFA) under UV and Visible illumination. In photocatalytic degradation studies, for both substrates, conversion rates of around 95% were found in 45 min of both UV-illumination and 85% under visible lighting. These conversion rates were superior than the conversion rates of pure parental components, AgBr and SnO<inf>2</inf> under the same experimental conditions. At least, for RhB no loss of photocatalytic activity has been observed after five recycles although the mineralization degree progressively diminished along the recycles. The enhanced photocatalytic degradation of AgBr/SnO<inf>2</inf> compounds was attributed, in part, to a synergistic increase in adsorption viability, as well as to the effective separation of photoinduced load carriers that resulted from the formation of a heterojunction according to the type II junction. Radical scavengers’ experiments indicated that active oxidant species as O<inf>2</inf>.<sup>−</sup>, ·OH and h<sup>+</sup> all are involved in this photocatalytic system, although it seems that O<inf>2</inf>.<sup>−</sup> played the major role in the photocatalytic degrading of RhB by AgBr/SnO<inf>2</inf> composites. In summary, coupling AgBr with SnO<inf>2</inf> remarkably improves the photocatalytic activity under both UV and visible-illumination with respect to the parental components. These features open the route to future applications of this material in the field of environmental remediation.