In-situ construction of Zr-based metal-organic framework core-shell heterostructure for photocatalytic degradation of organic pollutants

Abstract

Photocatalysis is an eco-friendly promising approach to the degradation of textile dyes. The majority of reported studies involved remediation of dyes with an initial concentration ≤50 mg/L, which was away from the existing values in textile wastewater. Herein, a simple solvothermal route was utilized to synthesize CoFe2O4@UiO-66 core-shell heterojunction photocatalyst for the first time. The photocatalytic performance of the as-synthesized catalysts was assessed through the photodegradation of methylene blue (MB) and methyl orange (MO) dyes at an initial concentration (100 mg/L). Under simulated solar irradiation, improved photocatalytic performance was accomplished by as-obtained CoFe2O4@UiO-66 heterojunction compared to bare UiO-66 and CoFe2O4. The overall removal efficiency of dyes (100 mg/L) over CoFe2O4@UiO-66 (50 mg/L) reached >60% within 180 min. The optical and photoelectrochemical measurements showed an enhanced visible light absorption capacity as well as effective interfacial charge separation and transfer over CoFe2O4@UiO-66, emphasizing the successful construction of heterojunction. The degradation mechanism was further explored, which revealed the contribution of holes (h+), superoxide (•O2−), and hydroxyl (•OH) radicals in the degradation process, however, h+ were the predominant reactive species. This work might open up new insights for designing MOF-based core-shell heterostructured photocatalysts for the remediation of industrial organic pollutants.

UiO-66-NDC (1,4-Naphthalenedicarboxylic Acid): A Versatile Metal-Organic Framework-Based Catalyst for Photocatalytic Degradation of Dye Chemicals

“…The pseudo first-order kinetics is a suitable representation as evidenced by the correlation constants' proximity to unity in Table 2. The obtained results are in agreement with the first-order pseudo-kinetic model [56,57]. Fig.…”

In situ heterojunction growth of CdS‐Bi2MoO6 microspheres for highly efficient photocatalytic degradation of Ciprofloxacin under visible light

“…It indicates that the charge transfer resistance at the interface of CdS‐BMO‐4 is minimal, and the recombination of electrons and holes is inhibited. The utilization of photoluminescence spectroscopy is common for the examination of the recombination process involving photogenerated carriers [41] . There is a negative correlation between the fluorescence intensity and the degree of complexation of excited state electron‐hole pairs [42] .…”

“…The utilization of photoluminescence spectroscopy is common for the examination of the recombination process involving photogenerated carriers. [41] There is a negative correlation between the fluorescence intensity and the degree of complexation of excited state electron-hole pairs. [42] In Figure 10c, the photoluminescence excitation wavelength is observed to be 375 nm.…”