Fabrication of superaerophobic Ru-doped c-CoSe2 for efficient hydrogen production

Transition metal dichalcogenides are recognized as promising electrocatalysts for hydrogen evolution reaction (HER), but their catalytic performances still require further enhancement. Herein, Ru-doped cubic CoSe2 with leaf-like microarray hollow structure supported on carbon cloth (Ru-c-CoSe2@CC) is rationally fabricated via a strategy involving in situ growth of Co-ZIF, Ru3+ ions etching and selenization steps. The chemical etching step transforms the precursor sample from Co-ZIF to RuCo-LDH and the subsequent selenization step observes crystal phase transformation and Ru-doping of CoSe2 to form Ru-c-CoSe2. Compared with orthorhombic CoSe2 and pristine c-CoSe2, the optimized electrocatalyst Ru-c-CoSe2/CC-3 shows significantly enhanced HER catalytic performance in both acidic and alkaline media. Theoretical investigations demonstrate the charge-transfer redistribution triggered by Ru dopants, optimizing the electronic states of the adjacent Co atoms with boosted intrinsic catalytic activity. Additionally, the leaf-like microarray hollow structure is highly desirable in active site expose and mass transfer due to its superaerophobic interfacial property.