Abstract

Over the last few years, photocatalytic titanium dioxide coatings have been explored in laboratory conditions tocreate building materials with self-cleaning and depolluting abilities. Assessing the performances of the photocatalyticsurfaces under real conditions may provide basic knowledge to evaluate the potential of real applicationsof TiO2 coatings in buildings.In this study, the performance of photocatalytic limestone surfaces obtained through coating with waterdispersedTiO2 nanoparticles were investigated in an urban environment. Coated and uncoated samples wereexposed to an urban site for one year. Before the exposure and periodically afterwards, optical microscopyobservations, colour and contact angle measurements were performed on the sample surface. At the end of theexposure period, samples underwent a capillary water absorption test and self-cleaning efficiency was evaluatedby a Rhodamine B photodegradation test. Ti and soluble fraction amounts on the sample surfaces were determinedby X-ray Fluorescence (XRF) and ion chromatography, respectively. The overall results showed theTiO2 coating was better able to preserve the surface colour properties early after exposure. After eight months,this effect was lost and the self-cleaning efficiency was reduced to negligible final rates. No clear wettabilityresults and no meaningful capillary behaviour were recorded. A decrease of the photocatalytic activity was dueto both partial titania loss and deactivation phenomena. The role of soluble salt ions either adsorbed from theenvironment or produced by the photocatalytic abatement of pollutants was recognized in the deactivation ofthe photocatalysts and their accumulation deserves attention for possible stone damage risk implications.

Autore Pugliese

• Calia Angela

Tutti gli autori

• M. Lettieri; D. Colangiuli; M. Masieri; A. Calia

Titolo volume/Rivista

Building and environment

Anno di pubblicazione

2018

ISSN

1873-684X

ISBN

Non Disponibile

Numero di citazioni Wos

Nessuna citazione

Ultimo Aggiornamento Citazioni

Non Disponibile

Numero di citazioni Scopus

Non Disponibile

Ultimo Aggiornamento Citazioni

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Settori ERC

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Codici ASJC

Non Disponibile