One-step ultrafast laser induced synthesis of strongly coupled 1T-2H MoS2/N-rGO quantum-dot heterostructures for enhanced hydrogen evolution

Strongly coupled transition-metal dichalcogenides/carbon hybrids are cost-effective and robust electrocatalysts for hydrogen evolution reaction, and further designing quantum-dot structures of hybrid catalysts often maximizes the accessible active sites and facilitates charge transfer and consequently their catalytic performance. However, the rational design and facile synthesis of such quantum-dot hybrid still remains a central challenge. Herein, an effective and controllable strategy is presented for one-step synthesis of strongly coupled 1T-2H MoS2/N-rGO quantum-dot heterostructures using spatially shaped laser ablation in liquid (LAL). The yield of QDs reaches 75.16 wt%, indicating that the mass production of such QDs is feasible using LAL method. Moreover, both characterizations and density functional theory calculations reveal that the much enhanced electrochemical HER performance arises from the optimized chemical composition, improved conductivity, and strongly coupled structural/electronic features. Correspondingly, the as-formed quantum-dot heterostructures exhibit remarkably low overpotential of 97 mV at 10 mA c2, a small Tafel slope of 39 mV dec-1 and high durability, outperformed most previously reported QDs-based electrocatalysts. This versatile strategy overcomes the current limitations of strong-coupled quantum-dot heterostructures materials preparing and offers a synergistic modulation approach for designing highly active HER catalysts viable for practical application.