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

Halim Lee; Hyungwoo Lee; Soyeon Ahn; Jooyoun Kim

doi:10.1021/acsomega.2c01953

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

ACS Omega. 2022 Jun 9;7(24):21145-21155. doi: 10.1021/acsomega.2c01953. eCollection 2022 Jun 21.

Authors

Halim Lee¹, Hyungwoo Lee^{2

3}, Soyeon Ahn¹, Jooyoun Kim^{1

4}

Affiliations

¹ Department of Textiles, Merchandising and Fashion Design, Seoul National University, Seoul 08826, Republic of Korea.
² Institute of Advanced Machines and Design, Seoul National University, Seoul 08826, Republic of Korea.
³ Division of Multiscale Mechanical Design, School of Mechanical and Aerospace Engineering, Seoul National University, Seoul 08826, Republic of Korea.
⁴ Research Institute of Human Ecology, Seoul National University, Seoul 08826, Republic of Korea.

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.