Electron-deficient naphthalenediimides modified g-C3N4 for boosting photocatalytic hydrogen evolution in freshwater and seawater

Abstract

Construction of a proper electron donor-acceptor (D-A) microenvironment through introducing a suitable chemical moiety is an effective strategy to facilitate photogenerated charge transfer in a cascade step actively, which can boost the corresponding photocatalytic performance significantly. Herein, a series of naphthalenediimide (NDI_y), possessing unique electron-deficient aromatic imides, were introduced to prepare D-A structured g-C₃N₄ (CN) derivative hybrid photocatalysts for photocatalytic hydrogen evolution (PHE) from water splitting. Remarkably, the modification with NDI_y all significantly improved the PHE performance, in which 1%NDI_NH2@CN exhibits the best photocatalytic activity (14.57 mmolꞏg⁻¹ꞏh⁻¹), exceeding 5.6 times over the unmodified pure CN under the same conditions. The enhanced PHE activity is highly associated with the interfacial D-A interactions between NDI_y and CN, which also lays the foundation for the further rational design of analogs toward various types of photocatalytic reactions.