Wettability, Photoactivity, and Antimicrobial Activity of Glazed Ceramic Tiles Coated with Titania Films Containing Tungsten

Self-cleaning coatings are advanced materials for the removal of pollutants and microorganisms by combining wettability, photocatalytic degradation, and antimicrobial activity. In this work, we propose a rational design of self-cleaning films based on TiO2 synthesized by sol-gel on commercial glazed...

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Bibliographic Details
Authors: Onna, Diego Ariel, Fuentes Flores, Keyla Mayerlin, Spedalieri, Ana Cecilia, Perullini, Ana Mercedes, Marchi, María Claudia, Alvarez, Fernando, Candal, Roberto Jorge, Bilmes, Sara A.
Format: article
Status:Published version
Publication Date:2018
Country:Argentina
Institution:Consejo Nacional de Investigaciones Científicas y Técnicas
Repository:CONICET Digital (CONICET)
Language:English
OAI Identifier:oai:ri.conicet.gov.ar:11336/88633
Online Access:http://hdl.handle.net/11336/88633
Access Level:Open access
Keyword:Wettability
Photoactivity
Antimicrobial
Titania Films
https://purl.org/becyt/ford/2.10
https://purl.org/becyt/ford/2
Description
Summary:Self-cleaning coatings are advanced materials for the removal of pollutants and microorganisms by combining wettability, photocatalytic degradation, and antimicrobial activity. In this work, we propose a rational design of self-cleaning films based on TiO2 synthesized by sol-gel on commercial glazed ceramic tiles for building's indoor applications. The synthesis strategy is based on hydrolysis and condensation of Ti-isopropoxide in the presence of W(VI) precursors to tune defects and crystallinity of the resulting W-TiO2 thin film. From the microstructure and surface composition analysis for different tungsten contents and annealing temperatures, we conclude that the film is composed by sintered TiO2 particles with adsorbed polytungstates (WOx) that inhibit anatase/rutile transformation. Polytungstates on TiO2 also induce surface defects that enhance water contact angle and inactivation of Escherichia coli under visible light. The presence of W(VI) has a negligible effect toward crystal violet degradation either under visible or under UV light. These results provide evidence on the existence of at least two different types of defects: (i) intrinsic defect from a sol-gel route and (ii) induced defect by tungsten species on the surface. Understanding the correlation between composition, structure, and self-cleaning properties provides a base for an efficient design of low-cost self-cleaning ceramic tiles that can be fully manufactured in an industrial plant.