To probe the origin of the improved activity for pN-C-supported catalysts, we conducted further characterization and analysis for Pt, Ru on pN-C and carbon. Hydrogen binding energy (HBE) is an important descriptor for HOR/HER . However, it has been recognized that HBE is not the only descriptor in alkaline media . Other factors such as water binding strength (also related to the apparent HBE, HBEapp) and OH binding energy (OHBE) are proposed to affect the kinetics of HOR/HER in alkaline medium. For example, the two orders of magnitude lower activity of Pt in alkaline medium than in acidic medium was attributed to either a too weak water binding strength (hence too strong HBEapp) or a too weak OHBE . In addition, the interfacial water structure was proposed to play a role by influencing the kinetic barrier of Volmer or Heyrovsky step . In view of these theories, we conducted experiments that could provide information on HBE, OHBE, water binding strength, and interfacial water structure.