Photoinduced Plasmon-Driven Chemistry in trans-1,2-Bis(4-pyridyl)ethylene Gold Nanosphere Oligomers.
Emily A Sprague-KleinBogdan NegruLindsey R MadisonScott C CosteBrandon K RuggAlanna M FeltsMichael O McAnallyMayukh BanikVartkess Ara ApkarianMichael R WasielewskiMark A RatnerTamar SeidemanGeorge C SchatzRichard P Van DuynePublished in: Journal of the American Chemical Society (2018)
Continuous wave (CW) pump-probe surface-enhanced Raman spectroscopy (SERS) is used to examine a range of plasmon-driven chemical behavior in the molecular SERS signal of trans-1,2-bis(4-pyridyl)ethylene (BPE) adsorbed on individual Au nanosphere oligomers (viz., dimers, trimers, tetramers, etc.). Well-defined new transient modes are caused by high fluence CW pumping at 532 nm and are monitored on the seconds time scale using a low intensity CW probe field at 785 nm. Comparison of time-dependent density functional theory (TD-DFT) calculations with the experimental data leads to the conclusion that three independent chemical processes are operative: (1) plasmon-driven electron transfer to form the BPE anion radical; (2) BPE hopping between two adsorption sites; and (3) trans-to- cis-BPE isomerization. Resonance Raman and electron paramagnetic resonance (EPR) spectroscopy measurements provide further substantiation for the observation of an anion radical species formed via a plasmon-driven electron transfer reaction. Applications of these findings will greatly impact the design of novel plasmonic devices with the future ability to harness new and efficient energetic pathways for both chemical transformation and photocatalysis at the nanoscale level.
Keyphrases
- electron transfer
- energy transfer
- raman spectroscopy
- density functional theory
- quantum dots
- ionic liquid
- sensitive detection
- molecular dynamics
- single molecule
- gold nanoparticles
- living cells
- label free
- molecular dynamics simulations
- visible light
- artificial intelligence
- atomic force microscopy
- electronic health record
- molecular docking
- deep learning
- mass spectrometry
- blood brain barrier
- genetic diversity