Promoting Piezocatalytic H2O2 Production in Pure Water by Loading Metal-Organic Cage-Modified Gold Nanoparticles on Graphitic Carbon Nitride
Graphical Abstract
A piezocatalyst for H2O2 production gives a yield of 120.21 μmol ⋅ g−1 ⋅ h−1 in pure water and air. The metal-organic cage (MOC) component enhances substrate (O2) and product (H2O2) adsorption via host–guest interaction and hinder the rapid H2O2 decomposition. The gold nanoparticle (AuNP) component affords a strong interfacial electric field that significantly promotes the migration of electrons from Graphitic carbon nitride (g-C3N4) component for O2 reduction reaction.
Abstract
Piezocatalytic hydrogen peroxide (H2O2) 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-C3N4) via hydrogen bond to serve as the multifunctional sites for efficient H2O2 production. Experiments and theoretical calculations prove that MOC-AuNP/g-C3N4 simultaneously optimize three key parts of piezocatalytic H2O2 production: i) the MOC component enhances substrate (O2) and product (H2O2) adsorption via host–guest interaction and hinders the rapid decomposition of H2O2 on MOC-AuNP/g-C3N4, ii) the AuNP component affords a strong interfacial electric field that significantly promotes the migration of electrons from g-C3N4 for O2 reduction reaction (ORR), iii) holes are used for H2O oxidation reaction (WOR) to produce O2 and H+ to further promote ORR. Thus, MOC-AuNP/g-C3N4 can be used as an efficient piezocatalyst to generate H2O2 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 H2O2 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 H2O2.
Conflict of interest
The authors declare no conflict of interest.
Open Research
Data Availability Statement
The data that support the findings of this study are available from the corresponding author upon reasonable request.
