Charge Engineering of Mo₂C@Defect-Rich N-Doped Carbon Nanosheets for Efficient Electrocatalytic H₂ Evolution

Charge engineering of carbon materials with many defects shows great potential in electrocatalysis, and molybdenum carbide (Mo₂C) is one of the noble-metal-free electrocatalysts with the most potential. Herein, we study the Mo₂C on pyridinic nitrogen-doped defective carbon sheets (MoNCs) as catalysts for the hydrogen evolution reaction. Theoretical calculations imply that the introduction of Mo₂C produces a graphene wave structure, which in some senses behaves like N doping to form localized charges. Being an active electrocatalyst, MoNCs demonstrate a Tafel slope as low as 60.6 mV dec^-1 and high durability of up to 10 h in acidic media. Besides charge engineering, plentiful defects and hierarchical morphology also contribute to good performance. This work underlines the importance of charge engineering to boost catalytic performance.