A Dicobalt Diammine Complex as an Efficient Ammonia Oxidation Electrocatalyst

Open AccessCCS ChemistryRESEARCH ARTICLES11 Sep 2025A Dicobalt Diammine Complex as an Efficient Ammonia Oxidation Electrocatalyst Chunyan Wang, Hui Jiang, Ronghuan Du, Jianzhe Li, Baomin Wang, Rong-Zhen Liao, Dawei Yang and Jingping Qu Chunyan Wang , Hui Jiang , Ronghuan Du , Jianzhe Li , Baomin Wang , Rong-Zhen Liao , Dawei Yang and Jingping Qu https://doi.org/10.31635/ccschem.025.202506203 SectionsSupplemental MaterialAboutPDF ToolsAdd to favoritesDownload CitationsTrack Citations ShareFacebookTwitterLinked InEmail Electrocatalytic ammonia oxidation (AO) to dinitrogen (N2) has attracted considerable attention due to its great promising application in fuel cells and significance for the ammonia economy. Recently, the development of molecular AO electrocatalysts has become a burgeoning research topic, especially based on earth-abundant metals. To date, several inexpensive metal complexes have been proven to be AO electrocatalysts, however, turnover frequency (TOF) and rate constant (kobs) are still less competitive than dominant ruthenium complexes. Herein, we designed and synthesized a novel thiolate-bridged dicobalt diammine complex [Cp*Co(μ-SEt)(NH3)]2[PF6]2 ( 1). Cyclic voltammetry and controlled potential electrolysis demonstrated complex 1 can mediate efficient electrocatalytic AO to N2, which exhibits the highest TOF of 45 h−1 among all molecular earthabundant metal catalysts and the highest kobs of 1.9×1011 M−1s−1 until now. Theoretical calculations proposed that this catalytic AO process may involve a crucial intermediate hydrazine complex [Cp*Co(μ-SEt)2(μ-η1:η1-NH2-NH2)CoCp*][PF6]2 ( 2) derived from an intramolecular N-N coupling pathway. Further studies indicate that complex 2 can also efficiently promote electrocatalytic AO to N2 with TOF of 24 h−1. This system represents the first cobalt complex that can achieve electrocatalytic AO, which provides a valuable strategy for the development of molecular electrocatalysts with high efficiency in the future. Download figure Download PowerPoint Previous articleNext article FiguresReferencesRelatedDetails Issue AssignmentNot Yet AssignedSupporting Information Copyright & Permissions© 2025 Chinese Chemical Society Downloaded 20 times PDF downloadLoading ...