Plasmonic Photoelectrochemistry: In View of Hot Carriers

Abstract

Utilizing plasmon‐generated hot carriers to drive chemical reactions has emerged as a popular topic in solar photocatalysis. However, a complete description of the underlying mechanism of hot‐carrier transfer in photochemical processes remains elusive, particularly for those involving hot holes. Photoelectrochemistry enables to localize hot holes on photoanodes and hot electrons on photocathodes and thus offers an approach to separately explore the hole‐transfer dynamics and electron‐transfer dynamics. This review summarizes a comprehensive understanding of both hot‐hole and hot‐electron transfers from photoelectrochemical studies on plasmonic electrodes. Additionally, working principles and applications of spectroelectrochemistry are discussed for plasmonic materials. It is concluded that photoelectrochemistry provides a powerful toolbox to gain mechanistic insights into plasmonic photocatalysis.

Electrochemical and Plasmonic Photochemical Oxidation Processes of para-Aminothiophenol on a Nanostructured Gold Electrode

“…1 Plasmonic photoelectrochemistry, by introducing an electric field into photochemical reactions, improves the reaction efficiency with the separation of hot electrons and holes. 2 Particularly, there have been numerous studies on the photoelectric synergistic effect. For example, plasmonic hot holes can effectively decrease the threshold potential of the aniline polymerization reaction.…”

“…Photochemical reactions mediated by hot carriers of plasmonic metal (e.g., Au, Ag, and Cu) nanoparticles are attractive in optical power conversion because of the surface plasmon (SPR) effect . Plasmonic photoelectrochemistry, by introducing an electric field into photochemical reactions, improves the reaction efficiency with the separation of hot electrons and holes . Particularly, there have been numerous studies on the photoelectric synergistic effect.…”

Enhancement of Plasmon‐Induced Photoelectrocatalytic Water Oxidation over Au/TiO2 with Lithium Intercalation

“…The plasmon‐induced electron‐hole separation and recombination were investigated through the open‐circuit potential ( V oc ) measurement under visible light irradiation, λ >480 nm (Figure 4d). Under SPR excitation, a cathodic V oc shift is observed for both Au/TiO 2 and Au/Li 0.2 TiO 2 , caused by the occupancy of TiO 2 conduction band (CB) with hot electrons transferred from Au NPs [19] . Under the open‐circuit condition, the photovoltage ( V ph ) results from the increased quasi‐fermi level of hot electrons ( E F, n ) relative to the equilibrium value ( E F , Redox ) obtained in the dark, described as Equation 1: [20] …”

Infrared surface plasmons on a Au waveguide electrode open new redox channels associated with the transfer of energetic carriers

“…Much of the work carried out to date in plasmonic catalysis involved colloidal arrangements of Au nanoparticles illuminated at visible wavelengths (e.g.,  0 = 532 nm, hυ = 2.33 eV) (4)(5)(6)(7)13). This scenario, although convenient, poses challenges.…”

“…Recently, attention has turned to investigating the role played by energetic carriers created by SPP absorption in electrochemical reactions ( 13 ). Advantageously, redox currents are easily measured, proportional to reaction rates, and directly connected to experimental conditions, including plasmonic effects.…”