Giant enhanced photocatalytic H2O2 production over hollow hexagonal prisms carbon nitride

Background H 2 O 2 , as a green and environmentally friendly oxidant, has been widely used in our daily life and industrial production. It is of epoch-making significance to develop highly efficient photocatalysts for producing H 2 O 2 . In recent years, g-C 3 N 4 has received much attention due to its high chemical stability, environmental friendliness and suitable energy band structure. However, some shortcomings including the fast recombination of photogenerated electron-hole pairs and small specific surface area in traditional 2D g-C 3 N 4 seriously impede its photocatalytic performance for the production of H 2 O 2 . Methods 1D hollow nanostructures possess intriguing physicochemical properties and are adopted to overcome the intrinsic shortcomings of g-C 3 N 4 . Herein, g-C 3 N 4 with a hollow hexagonal prism structure (CN HP) is prepared to produce H 2 O 2 . It is characterized by XRD, XPS, SEM, HRTEM, ESR and DRS. BET, PL spectra, photocurrent and EIS are used to explain the enhanced photocatalytic performance. Significant findings Compared with traditional 2D g-C 3 N 4 , the specific surface area of CN HP increases to 41.513 m 2 /g, providing more active sites. Meanwhile, its hollow tubular structure can enhance the migration of photogenerated electrons to the catalyst surface, and electrons with a longer lifetime can participate in photocatalytic reactions to achieve high efficiency. The yield of H 2 O 2 production can up to 4.08 μmol over CN HP in 40 min, which is about 7 times higher than that of traditional 2D g-C 3 N 4 , and the apparent quantum efficiency (AQE) of H 2 O 2 production at 420 nm is 2.41%. This research provides a valuable reference for the development of green materials for efficient photocatalytic production of H 2 O 2.