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

Abstract

Transition metal dichalcogenides are recognized as promising electrocatalysts for the hydrogen evolution reaction (HER), but their catalytic performances still require further enhancement. Herein, Ru-doped cubic CoSe₂ with a 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, and Ru³⁺ ion etching and selenization steps. The chemical etching step transforms the precursor sample from Co-ZIF into RuCo-LDH, and the subsequent selenization step leads to 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 exposure and mass transfer due to its superaerophobic interfacial properties.