Promoting Piezocatalytic H₂O₂ Production in Pure Water by Loading Metal‐Organic Cage‐Modified Gold Nanoparticles on Graphitic Carbon Nitride

Abstract

Piezocatalytic hydrogen peroxide (H₂ O₂ ) production is a green synthesis method, but the rapid complexation of charge carriers in piezocatalysts and the difficulty of adsorbing substrates limit its performance. Here, metal-organic cage-coated gold nanoparticles are anchored on graphitic carbon nitride (MOC-AuNP/g-C₃ N₄ ) via hydrogen bond to serve as the multifunctional sites for efficient H₂ O₂ production. Experiments and theoretical calculations prove that MOC-AuNP/g-C₃ N₄ simultaneously optimize three key parts of piezocatalytic H₂ O₂ production: i) the MOC component enhances substrate (O₂ ) and product (H₂ O₂ ) adsorption via host-guest interaction and hinders the rapid decomposition of H₂ O₂ on MOC-AuNP/g-C₃ N₄ , ii) the AuNP component affords a strong interfacial electric field that significantly promotes the migration of electrons from g-C₃ N₄ for O₂ reduction reaction (ORR), iii) holes are used for H₂ O oxidation reaction (WOR) to produce O₂ and H⁺ to further promote ORR. Thus, MOC-AuNP/g-C₃ N₄ can be used as an efficient piezocatalyst to generate H₂ O₂ at rates up to 120.21 μmol g^-1 h^-1 in air and pure water without using sacrificial agents. This work proposes a new strategy for efficient piezocatalytic H₂ O₂ synthesis by constructing multiple active sites in semiconductor catalysts via hydrogen bonding, by enhancing substrate adsorption, rapid separation of electron-hole pairs and preventing rapid decomposition of H₂ O₂ .