Kinetic Regularities of Photocatalytic Destruction of Cationic Dyes and Hydrogen Generation by Anatase-Based Binary Nanocomposites

Kinetic studies of the photocatalytic decomposition of cationic dyes MB (Methylene Blue) and RhB (Rhodamine B), and hydrogen generation from a water–methanol mixture were carried out using nanosized particles of anatase and binary composites based on it with 2 wt.% of palladium or cerium. Nanocomposites were synthesized by a chemical method using TTIP (Titanium TetraIsoPropoxide) in the presence of aqueous salt solutions containing doping metals. The paper briefly describes the structure, morphology, and chemical composition of the anatase-based nanoparticles using modern physical-chemical methods. In the presence of TiO 2 &Pd particles, the destruction degree of RhB and MB under the UV irradiation during 60 min reached 81.0–85.5%, and in the presence of TiO 2 &CeO 2 particles – 95%. The dye destruction process was accompanied by a hypsochromic shift of chromophoric peaks, which indicated the decomposition products formation. The reactions are pseudo-first order, and the rate constants are within 10 -2 . Photocatalytic activity for hydrogen generation using UV radiation showed increased activity (H 2 3519 μmol·g -1 ) for TiO 2 &2wt.%Pd due to the possible penetration of palladium atoms into the anatase lattice with efficient separation of photogenerated charge carriers in this system.