Ultrasmall Cu7S4@MoS2 Hetero-Nanoframes with Abundant Active Edge Sites for Ultrahigh-Performance Hydrogen Evolution

Increasing the active edge sites of molybdenum disulfide (MoS2) is an efficient strategy to improve the overall activity of MoS2 for the hydrogen-evolution reaction (HER). Herein, we report a strategy to synthesize the ultrasmall donut-shaped Cu7S4@MoS2 hetero-nanoframes with abundant active MoS2 edge sites as alternatives to platinum (Pt) as efficient HER electrocatalysts. These nanoframes demonstrate an ultra-high activity with 200 mAcm(-2) current density at only 206 mV overpotential using a carbon-rod counter electrode. The finding may provide guidelines for the design and synthesis of efficient and non-precious chalcogenide nanoframe catalysts.