Synthesis of para‐Amino Benzoic Acid–TiO₂ Hybrid Nanostructures of Controlled Functionality by an Aqueous One‐Step Process

In situ amino acid surface‐modified TiO 2 nanoparticle syntheses were performed by a simple one‐pot hydrolysis of heteroleptic titanium alkoxide [Ti(O i Pr) 3 (O 2 CC 6 H 4 NH 2 )] m in water with N n Bu 4 Br. This process allowed precise control of the surface grafting rate by varying the amount of precursors and provided highly functionalized nanomaterials. Their compositions and microstructures were determined by C, H and N elemental analyses, TGA‐MS, 13 C CP‐MAS NMR, XRD, TEM, BET, Raleigh diffusion, FTIR, Raman, XPS and UV/Vis experiments. The results indicated that (i) the aggregation rate increased with an increase in the loading of the organic substrate and (ii) the amino acid is chemisorbed as a carboxylate group onto the TiO 2 nanoparticles, which leads to a strong interaction between the amino acid and the TiO 2 nanoparticle and good stability of these hybrids. Applications of low‐aggregated nanomaterials were demonstrated as efficient protection additive against UVA + UVB radiations.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)