High-performance TiO2 catalyst composited with In–1,1,2,2-tetra(4-carboxylbiphenyl)ethylene for the efficient degradation of organic pollutants

Abstract

A combination of metal–organic frameworks (MOFs) with TiO₂ can improve the performance of TiO₂ in the photocatalytic degradation of organic pollutants. The selection of organic ligands for MOF preparation is a key factor for designing MOF–TiO₂ composites with excellent photocatalytic properties. However, the photocatalytic performance of such composites has rarely been examined. In this study, a series of TiO₂ nanoflowers (NFs) modified with In-based MOFs were prepared via a hydrothermal method using 1,1,2,2-tetra(4-carboxylbiphenyl)ethylene (TCBPE) as the organic ligand. The fabricated TiO₂@In–TCBPE (TIT) heterojunctions exhibited enhanced light absorption, charge separation, and electron transfer characteristics owing to the transport of ·O₂⁻ free radicals through the charge transfer pathway between heterostructures. Rhodamine B (RhB) was chosen as a typical representative of organic pollutants under simulated sunlight and is used to evaluate the photocatalytic performance of TIT composites. The optimized TIT composite exhibited a strong photocatalytic effect, and the complete degradation of RhB was achieved in 13 min. In addition, the prepared TIT composite demonstrated excellent photocatalytic activity during the degradation of organic pollutants in different aqueous environments (tap water, lake water, and river water). This study provides a reference for the selection of ligands for the subsequent construction of high-performance MOF photocatalysts.