Dominance of Plasmonic Resonant Energy Transfer over Direct Electron Transfer in Substantially Enhanced Water Oxidation Activity of BiVO₄ by Shape‐Controlled Au Nanoparticles

Abstract

The performance of plasmonic Au nanostructure/metal oxide heterointerface shows great promise in enhancing photoactivity, due to its ability to confine light to the small volume inside the semiconductor and modify the interfacial electronic band structure. While the shape control of Au nanoparticles (NPs) is crucial for moderate bandgap semiconductors, because plasmonic resonance by interband excitations overlaps above the absorption edge of semiconductors, its critical role in water splitting is still not fully understood. Here, first, the plasmonic effects of shape-controlled Au NPs on bismuth vanadate (BiVO ) are studied, and a largely enhanced photoactivity of BiVO is reported by introducing the octahedral Au NPs. The octahedral Au NP/BiVO achieves 2.4 mA cm at the 1.23 V versus reversible hydrogen electrode, which is the threefold enhancement compared to BiVO . It is the highest value among the previously reported plasmonic Au NPs/BiVO . Improved photoactivity is attributed to the localized surface plasmon resonance; direct electron transfer (DET), plasmonic resonant energy transfer (PRET). The PRET can be stressed over DET when considering the moderate bandgap semiconductor. Enhanced water oxidation induced by the shape-controlled Au NPs is applicable to moderate semiconductors, and shows a systematic study to explore new efficient plasmonic solar water splitting cells.

Ultrathin Lutetium Oxide Film as an Epitaxial Hole‐Blocking Layer for Crystalline Bismuth Vanadate Water Splitting Photoanodes

“…BiVO 4 (BVO) is a model photoanode material with several desirable characteristics, such as a moderate band gap of 2.4–2.6 eV with a conduction band edge that is close to hydrogen evolution potential, relatively long minority carrier diffusion length, and reasonable surface activity and stability . However, due to the notoriously low electron mobility of BiVO 4 , a back‐illuminated configuration is typically used, which generates photocarriers near the back contact.…”

Enhanced Electrocatalysis via Boosted Separation of Hot Charge Carriers of Plasmonic Gold Nanoparticles Deposited on Reduced Graphene Oxide

“…I-t curves were recorded at 0.35 V (vs Ag/AgCl) with light on and off in the presence of 30 mM glucose. EIS was recorded within the frequency range of 0.1-10 6 Hz with signal amplitude of 5 mV in 100 mM PBS buffer (pH 7.4) containing 30 mM Glucose. Laser light sources of 450, 532, 652, 808 nm were used .…”

“…The interaction of incident light with the metallic surface can excite resonant collective oscillations of conduction electrons of noble metal nanoparticles. [6][7][8][9] Therefore the plasmonic nanostructures have been widely used in photocatalysts, photodetectors, bioanalysis, enzyme-like, and construction of photovoltaic devices. It has been reported that the polarization of the electronic system leads to locally strongly enhanced electromagnetic fields and increased absorption cross section of plasmonic nanostructures.…”

“…[5] Moreover, by engineering the particle size, shape, material, and environment, the optical properties of the plasmonic nanomaterials can be tunable correspondingly. [6][7][8][9] Therefore the plasmonic nanostructures have been widely used in photocatalysts, photodetectors, bioanalysis, enzyme-like, and construction of photovoltaic devices. [10][11][12][13][14][15] Recently growing interests have been paid on the plasmonic nanostructures for both the fundamental studies and technological applications.…”

Photoelectrochemical Device Designs toward Practical Solar Water Splitting: A Review on the Recent Progress of BiVO4 and BiFeO3 Photoanodes

“…As a result of such efforts, a few candidates have been introduced and investigated extensively. The promising candidates are BiVO 4 [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24], Fe 2 O 3 [25][26][27][28][29][30][31][32], and BiFeO 3 [33][34][35]. Figure 2 shows the band gap energies and band edge positions of various semiconductors with respect to the water redox potential.…”