Highly Effective Photocatalytic Removal of Astrazon Blue, Allura Red, and Brilliant Blue Dyes From Aqueous Media Using a Stable Zr(IV)-Based Metal-Organic Frameworks

Abstract

Metal-organic frameworks (MOFs) have drawn considerable attention as promising photocatalysts due to their stability, reusability, tunability, and post-reaction separation capabilities. This study investigates the potential of UiO-66-NDC as a photocatalyst for the degradation of astrazon blue (AB), allura red (AR), and brilliant blue (BB) dyes. UiO-66-NDC was synthesized using a solvothermal method and characterized by PXRD, SEM, UV-DRS, FTIR, and zeta potential measurements. The photocatalytic activity of UiO-66-NDC revealed the degradation rates of 96% for AB within 45 min, 94% for BB within 90 min, and 91% for AB within 120 min at an optimal catalyst concentration of 300 mg/L. UiO-66-NDC demonstrated remarkable reusability over five consecutive cycles and maintained high degradation efficiency even at a high initial dye concentration of 20 mg/L with removal rates of 88% for AR, 85% for BB, and 81% for AB in the fifth cycle. A plausible photocatalytic mechanism has been proposed through trapping experiments of active species, identifying the reactive oxygen species as center dot OH radicals, enhancing the understanding of photocatalytic degradation. This study highlights the practical applicability of UiO-66-NDC in environmental remediation, emphasizing its potential as an efficient photocatalyst for the removal of various dyes from wastewater and industrial effluents.