MIL-100(Fe)-Hybridized Nanofibers for Adsorption and Visible Light Photocatalytic Degradation of Water Pollutants: Experimental and DFT Approach

Abstract

As rapid industrial growth spawns severe water contamination and a far-reaching impact on environmental safety, the development of a purification system is in high demand. Herein, a visible light-induced photocatalytic adsorbent membrane was developed by growing a porous metal–organic framework (MOF), MIL-100(Fe) crystals, onto electrospun polyacrylonitrile (PAN) nanofibers, and its purification capability by adsorption and the photocatalytic effect was investigated. As water-soluble organic foulants, a cationic dye, rhodamine B (RhB), and an anionic dye, methyl orange (MO), were employed, and the adsorption/desorption characteristics were analyzed. Since MIL-100(Fe) possesses positive charges in aqueous solution, MO was more rapidly adsorbed onto the MIL-100(Fe) grown PAN membrane (MIL-100(Fe)@PAN) than RhB. Under visible light, both photocatalytic degradation and adsorption occurred concurrently, facilitating the purification process. The reusability of MIL-100(Fe)@PAN as an adsorbent was explored by cyclic adsorption–desorption experiments. Density functional theory (DFT) calculations corroborated higher binding energy of charged MO over RhB and demonstrated the possible steric hindrance of RhB to adhere in MOF pores. The emphasis of the study lies in the combined investigation of the experimental approach and DFT calculations for the fundamental understanding of adsorption/desorption phenomena occurring in the purification process. This study provides theoretical support for the interaction between MOF–hybrid complexes and contaminants when MOF-hybridized composites adsorb or photodegrade water-soluble pollutants of different charges and sizes.

Curcumin/Zeolitic Imidazolate Framework-8 Nanoparticle-Integrated Microneedles for pH-Responsive Treatment of Skin Disorders

“…Among the tested, CCMZIF obtained from 0.008 g/mL of the CCM solution (LE ∼ 82.9%) was chosen for later experiments, as it had optimal LC, LE, and morphological characteristics. The TGA results in Figure S2 demonstrate a notable loading capacity of CCMZIF (∼40.2%) compared to devices fabricated in previous studies. ,, As a CCM molecule has a larger diameter (11.6 Å) than the pore size of pristine ZIF-8 (3.4 Å), the physical capture of CCM inside the pores of ZIF-8 is seemingly unstable. Instead, CCM will bond to the Zn 2+ ions of ZIF-8 by coordination. , During this process, CCMZIF can develop an enlarged particle (average diameter; 176 ± 45 nm) from the pristine ZIF-8 (average diameter; 128 ± 20 nm) (Figure e,f).…”

“…Among the tested, CCMZIF obtained from 0.008 g/mL of the CCM solution (LE ∼ 82.9%) was chosen for later experiments, as it had optimal LC, LE, and morphological characteristics. The TGA results in Figure S2 demonstrate a notable loading capacity of CCMZIF (∼40.2%) 45 compared to devices fabricated in previous studies. 36,38,44 As a CCM molecule has a larger diameter (11.6 Å) than the pore size of pristine ZIF-8 (3.4 Å), the physical capture of CCM inside the pores of ZIF-8 is seemingly unstable.…”

MOF‐Based Photocatalytic Membrane for Water Purification: A Review

“…Following multiple rinses, the SSM/UiO-66-NH 2 /CMn meshes were successfully obtained. Recently, Lee et al [149] developed a visible-light-driven photocatalytic adsorbent membrane through the growth of MIL-100(Fe) crystals onto electrospun PAN nanofibers. Firstly, they prepared PAN nanofiber membrane through electrospinning a prespinning solution containing trimesic acid (H 3 BTC) and PAN.…”

Recent Developments of Electrospinning-Based Photocatalysts in Degradation of Organic Pollutants: Principles and Strategies

“…In method 2, electrospun polymer nanofibers are utilize as a platform for synthesizing photocatalysts . Electrospun PAN nanofibers were dip coated in triethylamine and zinc acetate as a seed solution for ZnO .…”

“…In method 2, electrospun polymer nanofibers are utilize as a platform for synthesizing photocatalysts. 37 Electrospun PAN nanofibers were dip coated in triethylamine and zinc acetate as a seed solution for ZnO. 38 Then, growth of the ZnO nanorod occurred by immersing it in a mixed solution of zinc nitrate hexahydrate and hexamethylenetetramine.…”