Emerging Materials for Energy storage and environmental Research enabled through Atomic Layer Deposition, (EMERALD)

Stanford University, Stanford CA

Investigators

Abstract

There is a compelling need for an inexpensive, off-the-grid, technology in which solar energy is captured and used to produce a fuel - hydrogen - for heating and electricity when the sun does not shine and a disinfectant - hypochlorite (chemical formula NaOCl) - to create potable water. The worldwide need for potable water is great. A sixth of the world's population have no access to improved water supplies and far more consume contaminated water every day. This US-Republic of Ireland-Northern Ireland, United Kingdom research collaboration project involves harvesting the energy of sunlight to split saltwater into its chemical components: hydrogen, hypochlorite and another valuable product, caustic (NaOH). This technology is amenable to a modular system approach which would provide distributed power and potable water in areas with less infrastructure or during natural disasters. The project provides an international and multidisciplinary research experience for the involved students. The project also leverages Stanford's RISE outreach program to inspire students to consider further education and careers in the STEM fields using hands-on research experiences relevant to photovoltaics, motivated by the goal of advancing infrastructure in the developing world. This project is a multidisciplinary research project involving Stanford, Tyndall National Institute/University College Cork, Republic of Ireland and Queens University, Belfast, Northern Ireland United Kingdom. The collaboration involves multidisciplinary research on novel catalysts, corrosion protections layers for efficient earth-abundant light absorbers, and electrochemical cell design. Tasks will be performed on 1) new, inexpensive materials that enable efficient saltwater splitting, 2) methods for protecting silicon solar cell materials when they are exposed to saltwater, and 3) optimized designs for saltwater splitting devices. The project will investigate electrode materials selection and composition optimization, atomic layer deposition (ALD) methods to control local catalytic and electronic properties over highly porous electrodes, and the impact these factors have on cell efficiency and durability while minimizing platinum group metal use. The research will be related to two different devices, one an integrated and highly-efficient silicon photoelectrochemical cell, and the other an electrochemical cell which can be powered by an external photovoltaic array. A multiphysics modelling effort will inform the design details in order to optimize the cells for efficiency. Collectively, the team of researchers in the US, Ireland and Northern Ireland will assemble and test devices to demonstrate the performance and stability of the materials and device designs developed in this project. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.