After almost four decades, Leiden and Eindhoven chemists have resolved the discussion about the correct model regarding the simplest chemical reaction in heterogeneous catalysis, which is essential for fuel cells. Using a unique curved platinum surface, Ludo Juurlink and Ph.D. candidate Richard van Lent from Leiden and Michael Gleeson from DIFFER showed which model correctly describes the reaction of hydrogen. They published their findings in Science on 11 January.