Hot-Electron-Driven Interfacial Chemistry Using Non-Noble Plasmonic Cu under Visible-Light Irradiation

Abstract

Plasmon-excitation-driven hot electrons have been demonstrated to initiate chemical transformations when exposed to visible light. Nevertheless, achieving six-electron plasmon photocatalysis remains both rare and challenging due to the inability to maintain the persistent utilization of hot electrons. Moreover, plasmonic photocatalysts predominantly rely on noble metal nanomaterials, such as gold (Au) and silver (Ag) nanostructures. In this study, we explore the plasmonic catalysis of six-electron chemistry utilizing non-noble copper (Cu) nanoparticles under visible-light irradiation. Intriguingly, our findings reveal that in the absence of chemical reducing agents, cost-effective Cu nanoparticles can effectively catalyze the plasmonic conversion of 4-nitrothiophenol to 4-aminothiophenola transformation that remains unattainable for noble Au and Ag nanoparticles under identical conditions. Drawing upon the insights gleaned from in situ surface-enhanced Raman spectroscopy, we postulate that interfacial water (H2O) molecules compensate for the energetic hot holes generated on the plasmonic Cu surface, thereby furnishing an adequate supply of hot electrons required to activate the six-electron photocatalytic reaction. This research showcases the feasibility of multielectron photocatalysis chemistry employing earth-abundant Cu nanoparticles, thereby presenting promising opportunities for efficient solar-to-chemical energy conversion.

Molybdenum Disulfide Flakes as Platforms for the Photoconversion of 4-Nitrothiophenol

“…The characteristic modes of several molecules are detected with various intensities. The signals collected correspond to the previously observed DMAB but also to the 4-aminothiophenol (4-ATP) molecule …”

“…The signals collected correspond to the previously observed DMAB but also to the 4-aminothiophenol (4-ATP) molecule. 61 The characteristic Raman shifts of 4-ATP occurring in the [1580−1600] cm −1 region are attributed to the ωC�C wagging modes of the aromatic rings. 4-NTP, DMAB, and 4-ATP signals are collected, and point spectra are shown in Figure 6d.…”

Probing Oxidation Mechanisms in Plasmonic Catalysis: Unraveling the Role of Reactive Oxygen Species

“…For another, efficient oxidation of reactants on silver nanoparticles has been frequently reported in plasmonic catalysis, yet the underlying mechanisms remain unclear. , Though some attribute the oxidation to the plasmon-induced hot holes, − this hypothesis fails to withstand thorough scrutiny. In principle, silver tends to generate higher energy electrons and lower energy holes due to its Fermi level and band structures, which is contrast to gold tending to produce lower energy electrons and higher energy holes. , Therefore, attribution of the superior oxidizability of silver to plasmon-induced hot holes, which are expected to have low energy and limited oxidative capacity, appears unreasonable.…”