Toward enhanced photocatalytic activity of graphite carbon nitride through rational design of noble metal-free dual cocatalysts

Abstract

The g-C₃N₄-MoS₂-M(OH)_x ternary heterostructures were designed and fabricated for the first time. The embedding of noble-metal-free MoS₂-M(OH)_x dual cocatalysts over g-C₃N₄ nanosheets led to obvious synergistic effect for improving the transport as well as utilization efficiency of photo-generated charge carriers. Consequently, the optimal ternary heterostructure (g-C₃N₄-MoS₂-Ni(OH)₂) exhibited photocatalytic hydrogen production activity 4.5 times larger than the sum of the photocatalytic HER activity of g-C₃N₄-MoS₂ and g-C₃N₄-Ni(OH)₂. More significantly, even in the absence of the sacrificial agent, the g-C₃N₄-MoS₂-Ni(OH)₂ ternary heterostructure exhibited a photocatalytic HER activity of 0.3 mmol h⁻¹ g⁻¹ with considerable H₂O₂ production under UV-visible light.