Ethanol dehydrogenations on Cu(111), Cu3Pd(111), and Cu3Pt(111) were studied using density functional theory with a PBE functional. The alpha-C-H and beta-C-H scissions are endothermic on all surfaces while the O-H scission is exothermic on Cu(111) and Cu3Pt(111) but endothermic on Cu3Pd(111). The ethanol dehydrogenation occurs on Cu(111) through both alpha-C-H and O-H scissions but on Cu3Pd(111) and Cu3Pt (111) through only alpha-C-H scission. Furthermore, alloying Pt or Pd with Cu shows an increase in reaction rate at 493 K by more than 3 orders of magnitude, thus illustrating the promise of alloying Pt or Pd in Cu catalysts for ethanol dehydrogenation. (C) 2017 Elsevier B.V. All rights reserved.