Efficient and Stable Silicon-Based Solar Water Splitting Devices

Hydrogen production by solar water splitting has attracted considerable interests as a long-term energy storage system (ESS) to store intermittent solar energy to stable and reusable chemical fuels. While silicon is a promising material for photoelectrochemical (PEC) water splitting because of an earth-abundancy, low cost, and small bandgap, silicon has slow kinetics for hydrogen evolving reaction (HER). In addition, under conditions for oxygen evolution reaction, silicon easily forms an insulating SiO₂ or even corrodes. Therefore, new strategies are requires for stable and efficient silicon based PEC water splitting devices. In this talk, I’ll present our efforts to develop a silicon-based solar water splitting devices, leveraging the existing Si photovoltaic technology. Particularly, I’ll talk about nanoporous black Si to improve HER. In addition, I’ll present our novel device architecture to enhanced OER stability.