Capture, Store, and Discharge. Shuttling Photogenerated Electrons across TiO 2 –Silver Interface
Year: 2011
Type: article
Abstract: UV irradiation of TiO(2) nanoparticles in the presence of Ag(+) ions results in the quantitative reduction and deposition of silver on its surface. Continued UV irradiation following the deposition of Ag on the TiO(2) surface causes a blue shift in the surface plasmon peak from 430 to 415 nm as these particles become charged with excess electrons. Under UV irradiation, both the charging and discharging of electrons occur at different rates, thus allowing the system to attain a steady state. Upon stopping the UV irradiation, a fraction of these electrons remain stored. The electron storage is dependent on the amount of Ag deposited on TiO(2) nanoparticles with maximum capacity seen at 8.6 μM of Ag in a suspension containing 5.8 mM of TiO(2). Such electron charging and discharging processes in semiconductor-metal composites need to be taken into account while evaluating the plasmon resonance induced effects in photocatalysis and photoelectrochemistry.
Source: ACS Nano
DOI: 10.1021/nn202294b
Authors: Azusa Takai, Prashant V. Kamat
Institution: University of Notre Dame
Language: English
Field: Energy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2334288529