Effects of surface functionalization with alkylalkoxysilanes on the structure, visible light photoactivity and biocidal performance of Ag-TiO2 nanoparticles

Surface-modified Ag/TiO2 photocatalysts with enhanced activity under visible light and biocidal properties have been produced through a two-stage method involving the functionalization of TiO2 nanoparticles(NPs) with –SH or –NH terminated alkoxysilanes and deposition of AgNPs. The functionalization...

Descripción completa

Detalles Bibliográficos
Autores: Zarzuela, Rafael, Moreno-Garrido, Ignacio, Almoraima Gil, M. L., Mosquera, María J.
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2021
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/242733
Acceso en línea:http://hdl.handle.net/10261/242733
Access Level:acceso abierto
Palabra clave:Silver nanoparticles
Doped TiO2
Photocatalysis
Surface functionalization
Biocidal
Descripción
Sumario:Surface-modified Ag/TiO2 photocatalysts with enhanced activity under visible light and biocidal properties have been produced through a two-stage method involving the functionalization of TiO2 nanoparticles(NPs) with –SH or –NH terminated alkoxysilanes and deposition of AgNPs. The functionalization process increased the yield of the Ag deposition and promoted a more homogeneous distribution of the Ag over the TiO2 surface. The highest stability, homogeneity and visible range absorption was achieved by –NH functionalization. However, the modification with –SH groups alters the size of the AgNPs and decreases the effectiveness due to formation of Ag2S. The increased absorption in the visible spectrum accelerated the organic dye degradation under solar light, although aggregation processes affected their effectiveness under UV-A. The incorporation of AgNPs allowed for the elimination of phototrophic microorganisms under white light at very low Ag concentrations whereas TiO2 and –SH functionalized Ag/TiO2 showed no biocidal activity.