Preparation and photocatalytic performance of UIO-66/La-MOF composite

Abstract

To improve the photocatalytic degradation efficiency of photocatalytic materials UIO-66 and La-MOFs under visible-light irradiation, a series of photocatalytic materials with La and Zr as metal centers and terephthalic acid (H2BDC) and 2-amino terephthalic acid (H2ATA) as organic ligands were prepared by solvothermal method. The photocatalytic materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-visible (UV-vis) spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, and Mott-Schottky test. The photocatalytic degradation performance to Rhodamine B of the catalysts was fully investigated. Results show that the H2ATA series had stronger visible-light absorption capacity and better photocatalytic performance. The 0.35 La/Zr-H2ATA composite showed the best photocatalytic degradation. The quenching experiments confirmed that the active species in the photocatalytic degradation were the holes and superoxide radicals. The possible mechanisms of the carrier migration paths in the energy level matching for La/Zr-H2BDC and La/Zr-H2ATA were also discussed in detail. HIGHLIGHTS A heterojunction photocatalyst 0.35 La/Zr-H2ATA has been synthesized and it possesses excellent stability.; The 0.35 La/Zr-H2ATA photocatalysts exhibited the apparent visible-light absorption and the weakened recombination of photogenerated electron/hole pairs.; Two possible photocatalytic reaction mechanisms have been proposed.;

Keywords

• compound
• la-mofs
• photocatalytic oxidation
• rhodamine b
• uio-66