The synthesis of silver nanoparticles (AgNPs) within the interlayer space of transparent layered titania nanosheet (TNS) films is investigated. A considerable number of silver ions (≈70% against the cation exchange capacity of the TNS) are intercalated in the TNS films using methyl-viologen-containing TNSs as a precursor. The silver ion (Ag + )-containing TNS films are treated with aqueous sodium tetrahydroborate (NaBH 4 ), resulting in a gradual color change to bright blue. Various structural analyses clearly show that crystalline AgNPs are generated within the interlayer space of the TNSs. The NaBH 4 -treated films show intense and characteristic near-infrared (NIR) extinction spectra up to 1800 nm. The stability of the AgNPs within the TNS against oxygen and moisture is also investigated, and 96% and 82% of the AgNPs remain after standing in air for 1 month and 1 year, respectively. The NIR extinctions of the AgNP-containing TNS films are further extended by employing different preparation procedures, for example, using sintered TNS films as starting materials and irradiating the Ag + -containing TNSs with ultraviolet (UV) light. The obtained AgNP-containing TNS films exhibit photochemical activities in the production of hydrogen from ammonia borane under visible-light irradiation and the decomposition of nitrogen monoxide under UV-light irradiation. The synthesis of silver nanoparticles within the interlayer spaces of layered titanate films and their optical and photochemical characteristics are investigated. The films show intense extinction from the visible to the near-infrared region and exhibit good stability in air. The films exhibit photochemical activities for hydrogen production from amminetrihydridoboron and nitric oxide decomposition.
Energy, Environment Protection, Nuclear Power Engineering