Lee Halim, Lee Hyungwoo, Ahn Soyeon, Kim Jooyoun
Department of Textiles, Merchandising and Fashion Design, Seoul National University, Seoul 08826, Republic of Korea.
Institute of Advanced Machines and Design, Seoul National University, Seoul 08826, Republic of Korea.
ACS Omega. 2022 Jun 9;7(24):21145-21155. doi: 10.1021/acsomega.2c01953. eCollection 2022 Jun 21.
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.
随着快速的工业增长导致严重的水污染并对环境安全产生深远影响，对净化系统的需求很高。在此，通过在电纺聚丙烯腈（PAN）纳米纤维上生长多孔金属有机框架（MOF）MIL-100（Fe）晶体，开发了一种可见光诱导的光催化吸附膜，并研究了其通过吸附和光催化作用的净化能力。使用阳离子染料罗丹明B（RhB）和阴离子染料甲基橙（MO）作为水溶性有机污垢物，并分析了吸附/解吸特性。由于MIL-100（Fe）在水溶液中带正电荷，因此MO比RhB更快地吸附到生长有MIL-100（Fe）的PAN膜（MIL-100（Fe）@PAN）上。在可见光下，光催化降解和吸附同时发生，促进了净化过程。通过循环吸附-解吸实验探索了MIL-100（Fe）@PAN作为吸附剂的可重复使用性。密度泛函理论（DFT）计算证实了带电的MO比RhB具有更高的结合能，并证明了RhB在MOF孔中附着时可能存在的空间位阻。该研究的重点在于结合实验方法和DFT计算，以从根本上理解净化过程中发生的吸附/解吸现象。这项研究为MOF杂化复合物与污染物之间的相互作用提供了理论支持，当MOF杂化复合材料吸附或光降解不同电荷和尺寸的水溶性污染物时。
