Defective MoS2 electrocatalyst for highly efficient hydrogen evolution through a simple ball-milling method

Molybdenum disulfide (MoS2) has attracted extensive attention as an alternative to replace noble electro-catalysts in the hydrogen evolution reaction (HER). Here, we highlight an efficient and straightforward ball milling method, using nanoscale Cu powders as reductant to reduce MoS2 engineering S-vacancies into MoS2 surfaces, to fabricate a defect-rich MoS2 material (DR-MoS2). The micron-sized DR-MoS2 catalysts exhibit significantly enhanced catalytic activity for HER with an overpotential (at 10 mA cm(-2)) of 176 mV in acidic media and 189 mV in basic media, surpassing most of Mo-based catalysts previously reported, especially in basic solution. Meanwhile stability tests confirm the outstanding durability of DR-MoS2 catalysts in both acid and basic electrolytes. This work not only opens a new pathway to implant defects to MoS2, but also provides low-cost alternative for efficient electrocatalytic production of hydrogen in both alkaline and acidic environments.