Farah Naz, Chun Hong Mak, Zhe Wang, Haihang Tong, Shella Permatasari Santoso, Minshu Du, Ji-Jung Kai, Kuan-Chen Cheng, Chang-Wei Hsieh, Wenxin Niu, Zheng Hu, Hsien-Yi Hsu
Developing an economical and effective catalyst to remove organic pollutants from wastewater remains a significant challenge to maintaining a healthy, green environment. The metal-organic frameworks (MOFs) have drawn considerable attention to renewable energy and environmental remediation due to their porous crystalline structure. In this context, we develop a straightforward, environmentally friendly, solvent-free, in situ thermal (IST) method to synthesize doped zeolitic imidazole frameworks (ZIF-8). The solvent-free IST technique surpasses the traditional synthesis procedures in efficiency due to a single-step and solvent-free process with a short processing time and a low precursor ratio. Notably, doped ZIF-8 photocatalysts against concentrated methylene blue (MB) and rhodamine B (RhB) degradation exhibit superior photocatalytic performance under visible light exposure. An in-depth study of the effect of dye concentration and pH on doped ZIF-8 is also performed. The kinetic study via photocatalytic isotherms confirms that the photodegradation mechanism follows the pseudo-first-order kinetic model. Following active species trapping experiments, we confirm that the hydroxyl radicals play a substantial role in MB degradation with optimized Fe@ZIF-8. Moreover, the Fe@ZIF-8 does not significantly lose its photocatalytic activity for degrading MB after three cycles, indicating its enduring reusability and stability. Thus, this study provides a novel approach to developing the doped MOF as a photocatalyst with enhanced photocatalytic activity for wastewater treatment. © 2025 RSC.
School of Energy and Environment, Department of Materials Science and Engineering, Centre for Functional Photonics (CFP), City University of Hong Kong, Kowloon Tong, Hong Kong; Shenzhen Research Institute, City University of Hong Kong, Shenzhen, 518057, China; Department of Chemical Engineering, Faculty of Engineering, Widya Mandala Surabaya Catholic University, Kalijudan No. 37, East Java, Surabaya, 60114, Indonesia; School of Materials Science and Engineering, Northwestern Polytechnical University, Shaanxi, Xi'an, 710072, China; Department of Mechanical Engineering, City University of Hong Kong, Kowloon Tong, Hong Kong; Institute of Biotechnology, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei, 10617, Taiwan; Department of Optometry, Asia University, 500, Lioufeng Rd., Wufeng, Taichung, Taiwan; Department of Medical Research, China Medical University Hospital, China Medical University, 91, Hsueh-Shih Road, Taichung, Taiwan; Institute of Food Science and Technology, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei, 10617, Taiwan; Dept of Food Science, Fu Jen Catholic University, New Taipei City, 24205, Taiwan; Department of Food Science and Biotechnology, National Chung Hsing University, 145 Xingda Rd., South Dist., Taichung City, Taiwan; Department of Food Science, National Ilan University, Shennong Road, Yilan City, 26047, Taiwan; State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Jilin, Changchun, 130022, China; Key Laboratory of Mesoscopic Chemistry, MOE, Jiangsu Provincial Laboratory for Nanotechnology, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China; Department of Medical Research, China Medical University Hospital, Taichung City, Taiwan