Hydrogen production based on hexacoordinated cobalt scaffolds as electrocatalysts for acid-proton reduction: Electrochemistry and mechanisms

• Published in: Journal of electroanalytical chemistry (Lausanne, Switzerland) Switzerland), 2024-06, Vol.963, p.118228, Article 118228
• Main Authors: O. Shotonwa, Ibukun, Ejeromedoghene, Onome, O. Adesoji, Adedoyin, A. Alli, Yakubu, Akinremi, Caroline, Adewuyi, Sheriff
• Format: Article
• Language: English
• Subjects: Catalytic intermediates; Electrocatalytic proton reduction; Heterogeneous catalysis; Hydrogen economy; Hydrogenase
• ISSN: 1572-6657; 1873-2569
• DOI: 10.1016/j.jelechem.2024.118228

[Display omitted] •The use of carbon-based energy sources for fuel generation remains a major challenge.•Electrocatalytic production of H2 has evolved as a sustainable clean energy vector.•Cobalt complexes possess robust platforms for electrocatalytic designs in future.•Cobalt complexes are discussed from the perspective of electrochemistry, electrocatalysis and mechanistic pathways. The production of hydrogen as a fuel from the electrocatalytic reduction of protons is fast becoming a pivotal requirement for the future hydrogen economy that will provide lasting solutions to the environmental issues triggered by fossil fuel consumption and to meet the growing universal energy needs. The search for efficient catalysts based on earth-abundant transition metal complexes for the production of hydrogen was sequel to the paradigm shift from nature-inspired hydrogenase enzymes and heterogeneous platinum and rhodium catalysts due to their relative instability at reductive conditions and high cost respectively. From inception, focus has been on unsaturated systems especially the tetra- and penta-coordinated metal systems due to the availability of open sites for the double protonation sequence of the reduction catalytic cycle. However, saturated hexacoordinated cobalt complexes have opened the portal for determination of multiple catalytic pathways by their make and break hydride formation mechanism. These pathways are embodiment of catalytic intermediates, proton/electron transfer sequences as well as synergistic tendencies of experimental set up that can be assessed via experimental, spectroscopic, and theoretical methods.