title: Unraveling the Multiple Effects Originating the Increased Oxidative Photoactivity of {001}-Facet Enriched Anatase TiO2.
abstract: Crystal shape control on a series of anatase photocatalysts was achieved by varying the amount of HF employed as a capping agent in their hydrothermal synthesis. A systematic comparison between their physicochemical properties, determined by several complementary surface and bulk techniques before and after thermal treatment at 500 °C, allowed one to discern the influence of the relative amount of exposed {001} crystal facets among a series of effects simultaneously affecting their oxidative photocatalytic activity. The results of both formic acid and terephthalic acid photo-oxidation test reactions point to the primary role played by calcination in making {001} facets effectively photoactive. Annealing not only removes most of the residual fluorine capping agent from the photocatalyst surface, thus favoring substrate adsorption, but also produces morphological modifications to a crystal packing that makes accessible a larger portion of surface {001} facets due to the unpiling of platelike crystals. The photocatalyst bearing the highest amount of exposed {001} facets (60%) shows the highest photoactivity in both the direct and the (•)OH-radical-mediated photocatalytic test reaction.
authors.affiliation: Dipartimento di Chimica, Università degli Studi di Milano , via Golgi 19, I-20133 Milano, Italy.
authors.forename: Michela
authors.initials: M
authors.lastname: Maisano
authors.affiliation: Dipartimento di Chimica, Università degli Studi di Milano , via Golgi 19, I-20133 Milano, Italy.
authors.forename: Maria Vittoria
authors.initials: MV
authors.lastname: Dozzi
authors.affiliation: CNR-IENI Institute for Energetics and Interphases , Corso Promessi Sposi 29, I-23900 Lecco, Italy.
authors.forename: Mauro
authors.initials: M
authors.lastname: Coduri
authors.affiliation: Dipartimento di Scienze Chimiche, Università degli Studi di Padova , via Marzolo 1, I-35131 Padova, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Artiglia
authors.affiliation: Dipartimento di Scienze Chimiche, Università degli Studi di Padova , via Marzolo 1, I-35131 Padova, Italy.
authors.forename: Gaetano
authors.initials: G
authors.lastname: Granozzi
authors.affiliation: Dipartimento di Chimica, Università degli Studi di Milano , via Golgi 19, I-20133 Milano, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Selli
keywords: anatase {001} facets; holes; photocatalysis; photocatalytic oxidation; surface fluorination; •OH radicals