Unveiling the Promotion of Surface‐Adsorbed Chalcogenate on the Electrocatalytic Oxygen Evolution Reaction

Abstract Transition metal chalcogenides (TMCs) are efficient oxygen evolution reaction (OER) pre‐electrocatalysts, and will in situ transform into metal (oxy)hydroxides under OER condition. However, the role of chalcogen is not fully elucidated after oxidation and severe leaching. Here we present the vital promotion of surface‐adsorbed chalcogenates on the OER activity. Taking NiSe 2 as an example, in situ Raman spectroscopy revealed the oxidation of Se‐Se to selenites (SeO 3 2− ) then to selenates (SeO 4 2− ). Combining the severe Se leaching and the strong signal of selenates, it is assumed that the selenates are rich on the surface and play significant roles. As expected, adding selenites to the electrolyte…

• NN
  National Natural Science Foundation of China

  Awards: 21871206, 21901180
• NS
  Natural Science Foundation of Tianjin City

  Award: 17JCJQJC44700
• PR
  Postdoctoral Research Foundation of China

  Award: 2019TQ0226