Hierarchically Ordered Nanoporous Carbon with Exclusively Surface-Anchored Cobalt as Efficient Electrocatalyst

A hierarchically ordered porous carbon electrocatalyst with exclusively surface-anchored cobalt species, dubbed Co@HOPC, is synthesized from polyaniline and cobalt-functionalized silica microparticles templates, and its high electrocatalytic activity for the oxygen evolution reaction (OER) is demonstrated. The material requires a small potential (320 mV) to drive the reaction with a current density of 10 mA cm^-2 and a small Tafel slope of 31.2 mV dec^-1 . Moreover, Co@HOPC shows better catalytic activity for OER than in situ cobalt-doped and surface cobalt-loaded hierarchically ordered porous carbon materials synthesized by traditional methods. This is due to the abundant surface cobalt species present in Co@HOPC and the material's good electrical conductivity. This work provides a new strategy to utilize functionalized silica microparticles as templates to synthesize hierarchically ordered porous carbon materials with metal-rich surfaces and efficient electrocatalytic activities.