SnWO4 thin film photoelectrodes for solar water splitting
Solar water splitting offers a solution for solar energy storage problem, since the generated hydrogen can be stored as a renewable fuel. However, a suitable photoelectrode material for water oxidation reaction is still elusive. The reason for this is that the semiconducting materials have to meet the stringent requirements. For example, the elements of the electrode have to be earth-abundant and allow stability in aqueous solution. Furthermore, the photoelectrode has to absorb most of the visible spectrum of the sun to ensure a high solar-to-hydrogen efficiency.
In this work, a new promising n-type semiconductor α-SnWO4 was examined. This material absorbs most of the sunlight, due to its band gap of 1.5-1.7 eV. The SnWO4 films were prepared using Pulsed Laser Deposition (Figure 1). The oxygen pressure, temperature and laser fluence were systematically controlled to acquire the desired α-SnWO4 phase with optimized carrier transport properties (mobility, lifetime and diffusion length). Finally, the photoelectrochemical properties of the films were analyzed by measuring the photocurrent under AM1.5 solar simulator illumination.
Inês Jordão Pereira
University of Lisbon
HZB-Summer student 2017
Institute for Solar Fuels