Green Synthesis of Au-NPs on g-C₃N₄ Hybrid Nanomaterials Based on Supramolecular Pillar[6]arene and Its Applications for Catalysis

Gold nanoparticles (Au NPs) are installed in situ on the surfaces of graphitic carbon nitride (g-C3N4) based on supramolecular hydroxylatopillar[6]arene (P6). The Au NPs can be obtained via the redox reaction between HAuCl4 and P6 without any NH2–NH2, NaBH4, and other reductants, where AuCl4– is reduced to Au0 by the −OH groups in the presence of OH–, and the −OH groups are oxidized into −COOH. First, P6 is loaded onto the surface of g-C3N4 via π–π interaction between P6 and g-C3N4, which offers a stabilized and reduced site for in situ anchoring of Au NPs. The hybrid nanomaterial Au-NPs@P6@g-C3N4 exhibits higher catalytic capability than the Pd/C catalyst in 4-nitrophenol (4-NP) reduction and methylene blue degradation, which opens a new avenue for designing more efficient hybrid nanomaterials for application in catalysis, sensing, and other fields.