COBALT/NITROGEN-DOPED CARBONS AS EFFICIENT ELECTROCATALYSTS FOR HYDROGEN EVOLUTION REACTION

摘要

Replacement of precious platinum with efficient and low-cost catalysts for the electrocatalytic hydrogen evolution from water at low overpotentials holds tremendous promise for clean energy. Inspired by the naturally occurring hydrogen evolution and uptake on hydrogenase enzymes, chemists have made great breakthroughs in recent years on the development of bioinspired synthetic metal complex HER catalysts. Unfortunately, most bioinspired catalysts suffer from instability in aqueous solution and requirement of large overpotentials to achieve appreciable turnover frequencies (TOFs). Practical utilization of these synthetic molecular catalysts in fully aqueous electrolytes, therefore, requires careful grafting of them onto carbon nanotubes by additional and complex chemical processes. On the other hand, simultaneous but largely independent efforts in solid- state electrocatalysis have also led to several efficient inorganic crystalline catalysts. Despite of their promising performance, it is highly challenging to control the atomic-scale surface structure of these inorganic materials and to preferentially expose a greater fraction of the active sites, e.g. the edge sites of transition-metal dichalcogenides.