Chemistry Seminar - Improving Semiconductors for Solar Water Splitting Applications

The use of light-absorbing semiconductors to split water to produce H2 fuel is an appealing route to the renewable production of a chemical fuel which can be stored in large quantities much more easily than the electrical energy produced by photovoltaics or wind farms. While water-splitting activity has been demonstrated for numerous compounds, high overall efficiencies for this process remain an elusive goal – in part, because this activity is typically only achieved with ultraviolet light which represents less than 5% of terrestrial solar power. We will discuss recent results on some key materials which can split water with visible light, and our efforts to understand and improve their performance. Powder and single crystal work to prepare tunable systems in which the individual physical properties needed for good activities can be separately optimized will be discussed.