Morphological Engineering of Winged Au@MoS₂ Heterostructures for Electrocatalytic Hydrogen Evolution

Molybdenum disulfide (MoS₂) has been recognized as a promising cost-effective catalyst for water-splitting hydrogen production. However, the desired performance of MoS₂ is often limited by insufficient edge-terminated active sites, poor electrical conductivity, and inefficient contact to the supporting substrate. To address these limitations, we developed a unique nanoarchitecture (namely, winged Au@MoS₂ heterostructures enabled by our discovery of the "seeding effect" of Au nanoparticles for the chemical vapor deposition synthesis of vertically aligned few-layer MoS₂ wings). The winged Au@MoS₂ heterostructures provide an abundance of edge-terminated active sites and are found to exhibit dramatically improved electrocatalytic activity for the hydrogen evolution reaction. Theoretical simulations conducted for this unique heterostructure reveal that the hydrogen evolution is dominated by the proton adsorption step, which can be significantly promoted by introducing sufficient edge active sites. Our study introduces a new morphological engineering strategy to make the pristine MoS₂ layered structures highly competitive earth-abundant catalysts for efficient hydrogen production.