Integration of WOx/1D C3N4/2D C3N4 multi-junction through in-situ “PTA-Mel” ionic microenvironment for efficient aromatic wastes degradation via charge carrier separation improvement

Abstract

High photogenerated carrier recombination inhibits the widespread application of graphite-phase carbon nitride (g-C3N4). Construction of junctions is an effective strategy but still under challenges, such as tedious procedure and limited efficiency. Herein, WOx/1D g-C3N4/2D g-C3N4 multi-junction with enhanced separation of photogenerated carriers was one-pot integrated through in-situ “PTA-Mel” ionic microenvironment by mixing phosphotungstic acid (PTA) and melamine (Mel). Protonated Mel by PTA contributed to the formation of 1D g-C3N4 and the decomposition of [P(W3O40)4]3- produced WOx. 1D g-C3N4 and WOx with oxygen-vacancy deficient provided channels and caves for photoelectrons transfer, respectively. Compared with pure g-C3N4, the degradation rate constants of Rh B and tetracycline hydrochloride (TC) by WOx/1D g-C3N4/2D g-C3N4 are 2.34 and 1.45 times high respectively due to the excellent visible light absorption and improved photogenerated carrier separation. This method could be extended to the design of multiple heterojunctions in one photocatalyst through a facile process.