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0901-Ra05-18-Rb05-18.1

Crystalline TiO2 Macrocellular Foams with Highly Nano-Mesoporous Framework F. Carn1,*, S. Reculusa1, H. Deleuze2 and R. Backov1 1 Centre de Recherche Paul Pascal CNRS UPR 8641, 115 Ave Albert Schweitzer, 33600 Pessac, France ; 2 Laboratoire de Chimie Organique et Organométallique, UMR 5802-CNRS, Université Bordeaux 1, 351 Cours de la Libération, 33045 Talence Cedex, France. [email protected] ABSTRACT Titanium dioxide macro-cellular monolith-type materials have been obtained with emphases toward controlling porosity at the meso- and macroscopic length scales, leading thus to hierarchically organized porous architectures. First, at the microscopic length scale, either monophasic Anatase, biphasic Anatase-Rutile or monophasic Rutile allotropic forms are generated by varying the applied thermal treatment. At the meso- and/or nanoscopic length scales either lyotropic templates or latex colloids have been used to promote meso- or supermesoporosity. Particularly, a Pluronic copolymer P-123 combined with cationic surfactant (TTAB) induces vermicular-like mesoporosity associated with a specific surface area around 450 m2.g-1. At the macroscopic length scale a non-static air-liquid foam strategy allows a strong control over the open-cell morphologies. INTRODUCTION Promoting hierarchically organized monoliths appears today as a strong interdisciplinary field of research encompassing both the area of chemistry, physics, physical chemistry and biology. In this context of “chemistry of shapes” [1] or “synthesis over all length scales”[2] specific patterns can be used at different length scales. For instance, lyotropic mesophases can be employed at the mesoscale [2] while generating texturation at either nanoscale, using organic colloids [4], or at the macroscopic length scale playing this time with thermodynamically metastable systems such as, direct emulsions [5], reverse emulsions [6] or air-liquid foams [7]. In the air-liquid foam context we developed an air-liquid foaming process that allows design over both the macroscopic cell wall lengths, thicknesses and curvatures of silica macrocellular foams [7]. More recently, we extended this methodology, not based on a slurry method, toward other inorganic polymers such as V2O5 [8] and TiO2 [9]. In the later case, beyond tuning macroscopic void space morphologies, we varied also the cell wall topologies from smooth to fibrous-like or either ribbons-like textures. Designing accessible mesoporous network associated to monolithtype macrocellular networks confers additional advantages toward several specific properties applications ranging from bone-tissue implants catalysis and so forth [10]. In this present study, two types of texturating agent at the mesoscale were employed. First a lyotropic mesophase, i.e. pluronic non-ionic (P-123) surfactant was used while within a second experiment, latex colloidal nanoparticles were employed to enhance titanium dioxide mesoporosity or nanoporosity (above 10 nm). EXPERIMENTAL DETAILS Syntheses

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