One of the main obstacles in the production of hydrogen through water splitting is that hydrogen peroxide is also formed, which affects the efficiency stability of the reaction and the stability of the production. Dutch and Israelian researchers from Eindhoven University of Technology and the Weizmann Institute have succeeded in controlling the spin of electrons in the reaction and thereby almost fully suppress the production of hydrogen peroxide. They published these findings this week in the Journal of the American Chemical Society. The efficient production of hydrogen paves the way towards water splitting by solar energy.