Plasmonic photocatalysis

Abstract

Plasmonic photocatalysis has recently facilitated the rapid progress in enhancing photocatalytic efficiency under visible light irradiation, increasing the prospect of using sunlight for environmental and energy applications such as wastewater treatment, water splitting and carbon dioxide reduction. Plasmonic photocatalysis makes use of noble metal nanoparticles dispersed into semiconductor photocatalysts and possesses two prominent features-a Schottky junction and localized surface plasmonic resonance (LSPR). The former is of benefit to charge separation and transfer whereas the latter contributes to the strong absorption of visible light and the excitation of active charge carriers. This article aims to provide a systematic study of the fundamental physical mechanisms of plasmonic photocatalysis and to rationalize many experimental observations. In particular, we show that LSPR could boost the generation of electrons and holes in semiconductor photocatalysts through two different effects-the LSPR sensitization effect and the LSPR-powered bandgap breaking effect. By classifying the plasmonic photocatalytic systems in terms of their contact form and irradiation state, we show that the enhancement effects on different properties of photocatalysis can be well-explained and systematized. Moreover, we identify popular material systems of plasmonic photocatalysis that have shown excellent performance and elucidate their key features in the context of our proposed mechanisms and classifications.

Elucidating the real-time Ag nanoparticle growth on α-Ag2WO4during electron beam irradiation: experimental evidence and theoretical insights

“…2,10,12,16,[30][31][32] Specifically, plasmonic noble metal nanocrystals have recently been found to enhance a number of chemical reactions due to localized surface plasmon resonances. [33][34][35][36][37][38][39][40][41][42][43][44][45] However, the nature of the mechanism of the plasmonic driven chemistry in the presence of hot electrons or charged species and the concurrent photoluminescence properties over plasmonic particles are not well understood. 33,37,46,47 This investigation's motivation essentially arises from the discovery of an unwanted real-time in situ nucleation and growth of Ag filaments on a-Ag 2 WO 4 crystals which was driven by an accelerated electron beam from an electronic microscope under high vacuum.…”

Mechanism and experimental study on the photocatalytic performance of Ag/AgCl @ chiral TiO2 nanofibers photocatalyst: The impact of wastewater components

“…Two of the most important issues are (i) the reduction of the effective photocatalytic efficiency due to the competing electron-hole recombination process and (ii) the unsatisfactory visible-light response [4,5]. Some high-performance wide-gap photocatalysts such as TiO 2 and ZnO can only absorb UV light (wavelength < 400 nm), making them unattractive regarding the use of the full spectrum of solar light [6]. Numerous attempts have been made to overcome the above mentioned fundamental and technological barriers which are necessary to widen the practical range of applications of semiconductor photocatalysis.…”

Plasmon Mediated Photocatalysis by Solar Active Ag/ZnO Nanostructures: Degradation of Organic Pollutants in Aqueous Conditions

“…Among them, doping with a noble metal (Ag and Au) is the most sought after idea due to LSPR (a unique property of conduction band electrons of noble metals to oscillate by incident light). Noble metal doping also limits recombination of electron hole pairs [30] due to the formation of Schottky junction and such noble metal doped catalysts are sometime referred to as plasmonic photocatalysts thus silver has attracted much attention as dopant [31,32]. Ag doped ZnO has been studied by several researchers e.g.…”