Gram‐Scale Mechanochemical Synthesis of Atom‐Layer MoS₂ Semiconductor Electrocatalyst via Functionalized Graphene Quantum Dots for Efficient Hydrogen Evolution

Abstract The development of advanced and efficient synthetic methods is pivotal for the widespread application of 2D materials. In this study, a facile and scalable solvent‐free mechanochemical approach is approached, employing graphene quantum dots (GQDs) as exfoliation agents, for the synthesis and functionalization of nearly atom‐layered MoS₂ nanosheets (ALMS). The resulting ALMS exhibits an ultrathin average thickness of 4 nm and demonstrates high solvent stability. The impressive yield of ALMS reached 63%, indicating its potential for scalable production of stable nanosheets. Remarkably, the ALMS catalyst exhibits excellent HER performance. Moreover, the ALMS catalyst showcases exceptional long‐term durability, maintaining stable performance for nearly 200 h, underscoring its potential as a highly efficient and durable electrocatalyst. Significantly, the catalytic properties of ALMS are significantly influenced by ball milling production conditions. The GQD‐assisted large‐scale machinery synthesis pathway provides a promising avenue for the development of efficient and high‐performance ultrathin 2D materials.