Collectively exhaustive electrochemical hydrogen evolution reaction of polymorphic cobalt selenides derived from organic surfactants modified Co-MOFs

• DOI: 10.1016/j.apcatb.2023.122367
• Publication Date: 2023-01-03T16:41:34Z
• Authors: Pitchai Thangasamy; Rong He; Hyacinthe Randria...; Xinqi Chen; Yizhi Zhang; Hongmei Luo; Haiyan Wang; Meng Zhou
• Keywords: Selenide; Trimesic acid; Overpotential

Finding and exploring non-noble metal-based electrocatalysts for the promising power-to-hydrogen fuel technology through water splitting reactions is highly emerging. Herein, we report preparation of cobalt-based metal-organic frameworks (Co-MOFs) using an oleylamine (OLA) 1-dodecanethiol (DDT)-modified trimesic acid (TMA), cobalt precursor. Then, electrocatalytically active selenides were derived from Co-MOFs by a water-organic solvent mixture-assisted single-step selenization process. Interestingly, selenide obtained DDT-modified Co-MOF shows collectively exhaustive hydrogen evolution reaction (HER) performance with very small overpotentials ~161 ~206 mV to achieve 10 50 mA cm-2, respectively, due phase mixing characteristics synergistic interaction. The fast kinetics identified at DDT-Co electrode surface as confirmed observing lower charge-transport/interfacial resistance Tafel slope value high coverage adsorbed (Hads) atoms, evidenced interfacial chemical capacitance value, result electrical conductivity large electrochemically accessible sites. calculated activation energy (Ea) HER further reveals low kinetic barrier in on selenide, indicating intrinsic catalytic activity diffusion rate Hads. Furthermore, cathodic transfer coefficient (αc) strongly suggested that (αc = 2) proceeds Langmuir-Hinshelwood mechanism follows Volmer-Tafel pathway. present work provides valuable insights into modification their impact also mechanistic investigation based electrochemical impedance spectroscopy analysis.