A ternary C-SnO2–g-C3N4–MoS2 heterostructure for highly efficient photo/electrocatalytic hydrogen production†

This work reported the design and fabrication of a ternary heterostructure for efficient photocatalytic and electrocatalytic hydrogen production. Here, the C-SnO₂–g-C₃N₄–MoS₂ heterostructure with unique electronic and optical properties is developed using a simple two-step synthesis strategy, in which first a C-doped SnO₂ nanostructure (C-SnO₂) was prepared by thermal decomposition and then a hybrid ternary heterostructure of C-SnO₂ with layered 2D materials g-C₃N₄ and MoS₂ was developed by using a simple solution chemistry approach. The reported C-SnO₂–g-C₃N₄–MoS₂ hybrid heterostructure exhibited an enhanced photocatalytic activity of 11.85 mmol g⁻¹ hydrogen production and 17.21% apparent quantum efficiency (AQE) due to improved catalytically active sites, boosted charge transfer efficiency at the interface, suppression of charge carrier recombination, and synergistic interaction between the components. Moreover, the C-SnO₂–g-C₃N₄–MoS₂ heterostructure material showed outstanding electrocatalytic activity for hydrogen production (HER), requiring an overpotential of −0.18 V vs. RHE to accomplish a current density of 10 mA cm⁻². The superior HER performance of the heterostructure is ascribed to its more electrochemically active surface sites, combined with the synergistic interaction among its components.