Enhanced solar water splitting using plasmon-induced resonance energy transfer and unidirectional charge carrier transport

Abstract

Solar water splitting by photoelectrochemical (PEC) reactions is promising for hydrogen production. The gold nanoparticles (AuNPs) are often applied to promote the visible response of wideband photocatalysts. However, in a typical TiO2/AuNPs structure, the opposite transfer direction of excited electrons between AuNPs and TiO2 under visible light and UV light severely limits the solar PEC performance. Here we present a unique Pt/TiO2/Cu2O/NiO/AuNPs photocathode, in which the NiO hole transport layer (HTL) is inserted between AuNPs and Cu2O to achieve unidirectional transport of charge carriers and prominent plasmon-induced resonance energy transfer (PIRET) between AuNPs and Cu2O. The measured applied bias photon-to-current efficiency and the hydrogen production rate under AM 1.5G illumination can reach 1.5% and 16.4 μmol·cm-2·h-1, respectively. This work is original in using the NiO film as the PIRET spacer and provides a promising photoelectrode for energy-efficient solar water splitting.

Plasmonic Solar Energy Harvesting by ZnO Nanostructures and Their Composite Interfaces: A Review on Fundamentals, Recent Advances, and Applications

“…Therefore, for the PIRET the intermetal NS separation is a vital parameter. [18,37,46,[75][76][77] 2.4. Mechanism of PEC Solar PEC hydrogen production is one of the most attractive technologies that could potentially give a clean, cost-effective, and domestically produced energy carrier by taking advantage of the 1 20 000 TW of radiation that continually strikes the Earth's surface.…”

Hole Transport Layer in Photoelectrochemical Water Splitting

“…[63] The second type of the photocathode hole transport system (Figure 5b) mainly consists of a conductive substrate, a HTL, a photocatalyst, and a hydrogen evolution cocatalyst. [73][74][75][76][77][78][79][80][81] For an unstable photocatalytic systems, a protective layer is often added between the photocatalyst and the cocatalyst. [73,76,77] Furthermore, most of the cocatalysts in this system are platinum, which not only provides surface redox sites and increases hydrogen production, but also collects electrons and promotes carrier transport.…”