Solar hydrogen

The most promising method of hydrogen generation using a renewable energy source is taht based on solar photo electrochemical (PEC) water decomposition on a semiconductor surface. Current methods and devices to produce hydrogen from water and sunlight are yet inefficient, and consequently the price of solar hydrogen is too high. Within this project, we address several weaknesses of current water splitting schemes, including limited light absorption in the visible, difficulties of matching the semiconductor bandedges with the water redox potentials, and fast electron-hole recombination. We approach these challenges by combining thoretical and experimental efforts and utilizing advanced concepts from materials science, nanoscience and nanotechnology and physics. The experimental groups will focus on identifying, synthesizing and characterizing novel semiconductor materials for water splitting (SrTiO-, InTaO- and ZnO-based materials with appropriate surface coatings), both in the form of thin films and as nanostructures, and studying their optical and photoelectrochemical properties. Additionally, these semiconductors materials will be functionalized with (metallic) nanostructures, which are capable of harvesting a large fraction of the visible light through particle plasmon excitations, and the coupling of such excitations with waveguiding modes in the underlying semiconductor support will be invenstigated. The focus of the theory groups will be on determining relevant properties of and electronic excitations in promising materials using self-interaction corrected DFT calculations and to predict novel, interesting material compositions. Based on our experimental and theoretical findings, we aim to prepare and test a demonstrator device which implements the most successful schemes to result in the best possible performance