Technion researchers have invented a new method that separates hydrogen production from oxygen production in the water splitting process using solar energy. This innovation will facilitate the centralized, safe and efficient production of hydrogen on tap.
Publishing in Nature Materials, the researchers envision hydrogen production at the point of sale (for example, at a gas station for electric cars fueled by hydrogen) located far from the solar farm. The technology is forecast to significantly reduce the cost of producing the hydrogen and shipping it to the customer.
Hydrogen is considered one of the most promising fuel alternatives because it can be produced from water, and therefore production does not depend on access to non-renewable natural resources. Most hydrogen is currently produced from natural gas in a process that emits carbon dioxide into the atmosphere, but it is also possible to produce hydrogen from water by splitting the water molecules into hydrogen and oxygen in a process called electrolysis. However, since electricity production itself is an expensive and polluting process, global research is exploring a photoelectrochemical (PEC) cell that uses solar energy to split water into hydrogen and oxygen directly, without the need for external power source.
The main challenges in the development of PEC solar farms for the production of hydrogen are keeping the hydrogen and the oxygen separate; collecting the hydrogen from millions of PEC cells; and transporting the hydrogen to the point of sale.
The Technion team solved these challenges by developing a new method for PEC water splitting. With this method,
The hydrogen and oxygen are formed in two separate cells – one that produces hydrogen, and another that produces oxygen, avoiding the risk of a flammable and explosive mixture.
The study was led by Avigail Landman, a doctoral student in the Nancy and Stephen Grand Technion Energy Program (GTEP). Landman is working on her doctorate under the guidance of Prof. Avner Rothschild from the Faculty of Materials Science and Engineering,and Prof. Gideon Grader, Dean of the Wolfson Faculty of Chemical Engineering.
“According to our cost estimate, our method could successfully compete with existing water splitting methods and serve as a cheap and safe platform for the production of hydrogen,” says Landman.
Prof. Gideon Grader holds the Arturo Gruenebaum Chair in Materials Engineering