The unique ability of plasmonic nanoparticles to localize and enhance resonant electromagnetic fields has enabled a wealth of discoveries from enhanced spectroscopies to driving chemical reactions on the nanoscale. In this thesis, we strive to both drive and observe chemistry on plasmonic surfaces. First, we examine the possibility of driving the environmentally relevant reaction of carbon dioxide reduction to carbon monoxide using a plasmon driven electrochemical system. Then the interplay between hot carrier transfer and local heating are investigated during the process of plasmon driven ferrocyanide oxidation using environmental temperature control. Efforts towards driving and observing plasmon driven chemistry with ultrafast laser excitation were made, but ultimately the frequency and efficiency of plasmon driven reactions limited these attempts. With this in mind, we demonstrate time resolved surface-enhanced femtosecond stimulated Raman spectroscopy (SE-FSRS) using the time dependent response of the gold nanoparticle oligomers to plasmon excitation. This appears as transient depletion in the SE-FSRS gain that recovers over the course of picoseconds. The final work presented uses excitation dependent Raman spectroscopy to probe the hybrid resonances of a strongly couple j-aggregate/plasmon system. In this experiment we find that while the UV-vis extinction measurements show large Rabi splitting, the Raman excitation profiles largely peak between the two split resonances indicating the largest degree of molecule plasmon interaction lies near the original contributing resonances. With this work we hope to advance the field of plasmonics by enabling new spectroscopic techniques and providing insight towards the mysteries of plasmon driven chemistry.

Creator

• Ueltschi, Tyler W

DOI

• https://doi.org/10.21985/n2-hx1b-dp31

Subject

• Physical chemistry

Language

• en

Alternate Identifier

• etdadmin_upload_723530
• http://dissertations.umi.com/northwestern:15027

Keyword

• ultrafast
• plasmon
• Raman
• spectroscopy
• nanoparticles
• plasmonics

Date created

• 2020-01-01

Resource type

• Dissertation

Rights statement

• In Copyright