Electrostatic self-assembled layered polymers form supramolecular heterojunction catalyst for photocatalytic reduction of high-stability nitrate in water

Abstract

In this work, two polymers are connected by electrostatic self-assembly method to form a supramolecular heterojunction to remove pollutants. g-C3N4-Cl/PANI catalyst can be used for photocatalytic reduction of nitrate in water, and the nitrogen selectivity reaches 98.2%. Specially, charge density analysis and comparative experiments showed that the introduction of covalent chlorine increased in electron transfer conduction between layers. In addition, differential charge density and solid EPR tests reveal high electron density and electron transfer pathways for supramolecular heterostructures. The results of the work function give direct evidence for the high catalytic performance of the supramolecular heterojunction. The reasons and active species of photocatalytic reduction of nitrate by g-C3N4-Cl and g-C3N4-Cl/PANI are compared. The catalyst exhibits the performance of highly reducing nitrate to harmless nitrogen with the contribution of supramolecular heterojunction and covalent chlorine. In short, a new idea of constructing a supramolecular photocatalyst is proposed, which can be applied to efficiency reduce nitrate in water.