Ultrafast dynamics of photoexcited electrons in Ag nanoplatelets adsorbed on TiO2 nanorods, a material that may have potential for photosensitized voltaic applications is studied using femtosecond transient infrared (IR) absorption spectroscopy. Hot electrons are generated in Ag nanoplatelets through plasmonic excitation by a femtosecond light pulse at 400 nm. Injection of the photoexcited electrons and the following dynamics processes in TiO2 nanorods, in the conduction band, are probed by the absorption of femtosecond pulses in the mid-IR range with varying time delay. The observed transient absorption response is analyzed by a model that includes hot electron injection, hot electron relaxation, band-edge electron annihilation, electron diffusion from the surface to bulk, and electron back diffusion from bulk to surface. The corresponding time constants are extracted to be around 13 fs, 0.8 ps, 6 ps, 14 ps, and 70 ps, respectively. It is significant to note that the electron injection from the Ag platelets is occurring at a rate much faster than that from Au to TiO2, which is one order of magnitude faster than that from dye molecules to the semiconductor. The characterization of the electron dynamics is useful for mechanistic understanding and designing of efficient photovoltaic and photocatalysis materials.

Photoexcited electron dynamics in Ag nanoplatelets adsorbed on TiO2 nanorods

Macromolecular Chemistry: The Second Century

[Author Benefits](https://scimeetings.acs.org/?utm_source=pubs_content_marketing&utm_medium=website&utm_campaign=0320_MCF_NPI_Launch_Spring_Homepage&ref=pubs_content_marketing)

[How to use SciMeetings](https://storage.googleapis.com/dl.morressier.com/acs/SciMeetings-ACSSpring2020-HowToGuide_M3020-Final.pdf)

[Frequently Asked Questions](https://storage.googleapis.com/dl.morressier.com/acs/SciMtng_ACSNMSp2020_FAQ_M3120_Final.pdf)

ACS Spring 2020 National Meeting & Expo

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.