Review of Experimental Setups for Plasmonic Photocatalytic Reactions

Abstract

Plasmonic photocatalytic reactions have been substantially developed. However, the mechanism underlying the enhancement of such reactions is confusing in relevant studies. The plasmonic enhancements of photocatalytic reactions are hard to identify by processing chemically or physically. This review discusses the noteworthy experimental setups or designs for reactors that process various energy transformation paths for enhancing plasmonic photocatalytic reactions. Specially designed experimental setups can help characterize near-field optical responses in inducing plasmons and transformation of light energy. Electrochemical measurements, dark-field imaging, spectral measurements, and matched coupling of wavevectors lead to further understanding of the mechanism underlying plasmonic enhancement. The discussions herein can provide valuable ideas for advanced future studies.

Au@Ag Dendritic Nanoforests for Surface-Enhanced Raman Scattering Sensing

“…Step (ii) is related to the polarizability of the surface-molecule complex as chemically or physically accepting the energy from the illumination light. Step (iii) is associated with the inelastic decay of generated plasmons, or focused light of hot spots of localized oscillating electrons, delivering or acquiring energy from the target material, e.g., R6G in this work, in Raman scattering measurements [ 49 ]. Steps (i) and (iii) are related to the plasmonic property of the SERS sensor (e.g., rough metal surfaces, metal NPs, periodical metal structures, or metal networks of metal nanowires or nano branches).…”

Hybrid Plasmonic Nanomaterials for Hydrogen Generation and Carbon Dioxide Reduction

“…Despite being a young field, there are already several reviews, 13 − 15 perspectives, 16 − 18 and even a book 19 covering different topics of the area. Some focus on the theoretical aspects and the working mechanisms of plasmonic photocatalysis.…”

Phonon-Assisted Hot Carrier Generation in Plasmonic Semiconductor Systems

“…The free carriers detected by TIRAS in the Au/TiO 2 system following plasmon excitation can have three origins: (i) plasmonic scattering and trapping; (ii) plasmon-induced energy transformation; and (iii) plasmon-induced hot carrier generation. , Processes (i) and (ii) generate electron–hole pairs directly on the semiconductor, while process (iii) generates hot carriers on the plasmonic structure which subsequently can transfer the semiconductor. The type of injected carrier depends on band alignments which for the present system should be hot electrons injecting into the TiO 2 conduction band (CB).…”