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 electrocatalysts 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 defectrich 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.