Electronically Integrated Mesoporous Ag–TiO<sub>2</sub> Nanocomposite Thin films for Efficient Solar Hydrogen Production in Direct Sunlight
Sunesh S. Mani, Sivaraj Rajendran, Naresh Nalajala, Thomas Mathew, Chinnakonda S. Gopinath
Abstract
The synthesis of mesoporous TiO 2 by a solution‐based assembly process and Ag/TiO 2 nanocomposites is provided. The efficacy of Ag/TiO 2 nanocomposite as photocatalyst in thin‐film form is demonstrated for solar hydrogen generation in sunlight. Integration of Ag with TiO 2 dramatically enhanced the H 2 production: with 1 wt% Ag on TiO 2 (TiAg‐1), the H 2 yield was observed to be 4.59 mmol h −1 g −1 , which is 2.3 (30) times larger than 0.5 wt% Ag on TiO 2 . TiAg‐1 shows 4.3 times higher activity in film form compared with its powder counterpart. High photocatalytic efficiency is attributed to the surface plasmon resonance effect of Ag, electronic integration of Ag with TiO 2 , and subsequent valence band broadening, large distribution of Ag nanoparticles and abundant Ag‐TiO 2 Schottky junctions, and the later minimizes electron–hole recombination. Interparticle mesoporous network increases necking and the high surface area offers easy accessibility of the reactants to a large number of active sites.