Natural molybdenite mineral enhanced polymeric carbon nitride nano-composites for efficient noble-metal-free photocatalytic hydrogen evolution

Photocatalytic hydrogen evolution reaction (HER) is an ideal strategy to convert solar energy into chemical energy, while the efficiency is suppressed by limited light absorption, charge carrier separation and transfer, and interface reaction. Polymeric carbon nitride (PCN) as a metal-free visible-light photocatalyst has attracted increasing attention. However, expensive noble metal such as Pt nanoparticles are generally needed to co-catalyze HER on PCN and other photocatalysts. Herein, natural molybdenite mineral was introduced for the first time as co-catalyst to construct PCN/molybdenite nano-composites (PCN/Mo-x) by Na₂SO₄-assisted ball milling, which displayed a favorable noble-metal-free photocatalytic HER rate under visible light. Molybdenite not only replaced Pt co-catalyst to promote the separation efficiency of photo-induced electrons and holes but also enhanced the light absorption, synergistically increasing photocatalytic activities of PCN. The proposed path may pave the way to utilize the cheap minerals as promising candidates for co-catalysts in noble-metal-free photocatalysis on PCN and/or other photocatalysts.