Fast and Facile Synthesis of Cobalt-Doped ZIF-8 and Fe3O4/MCC/Cobalt-Doped ZIF-8 for the Photodegradation of Organic Dyes under Visible Light

Amin Mehrehjedy; Piyush Kumar; Zachary Ahmad; Penelope Jankoski; Anuraj S Kshirsagar; Jason D Azoulay; Xuyang He; Mahesh K Gangishetty; Tristan D Clemons; Xiaodan Gu; Wujian Miao; Song Guo

doi:10.1021/acsomega.4c06142

Fast and Facile Synthesis of Cobalt-Doped ZIF-8 and Fe₃O₄/MCC/Cobalt-Doped ZIF-8 for the Photodegradation of Organic Dyes under Visible Light

ACS Omega. 2024 Dec 7;9(50):49239-49248. doi: 10.1021/acsomega.4c06142. eCollection 2024 Dec 17.

Authors

Affiliations

¹ Department of Chemistry and Biochemistry, School of Mathematics and Natural Sciences, University of Southern Mississippi, Hattiesburg, Mississippi 39406, United States.
² School of Polymer Science and Engineering, The University of Southern Mississippi, Hattiesburg, Mississippi 39406, United States.
³ Department of Chemistry, Mississippi State University, Starkville, Mississippi 39762, United States.
⁴ School of Chemistry and Biochemistry and School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States.
⁵ School of Criminal Justice, Forensic Science, and Security, The University of Southern Mississippi, Hattiesburg, Mississippi 39406, United States.
⁶ Department of Physics and Astronomy, Mississippi State University, Mississippi State, Mississippi 39762, United States.

Abstract

Co-doped ZIF-8 as a water-stable visible light photocatalyst was prepared by using a one-pot, fast, cost-effective, and environmentally friendly method. The band structure of ZIF-8 was tuned through the incorporation of different percentages of cobalt to attain an optimal band gap (E _g) that enables the activation of ZIF-8 under visible light and minimizes the recombination of photogenerated charge carriers. A magnetic composite of Co-doped ZIF-8 was also synthesized to facilitate catalyst recycling and reusability through the application of an external magnetic field. Surface modification of magnetic Fe₃O₄ nanoparticles with microcrystalline cellulose (MCC) was used to reduce the level of agglomeration. The photocatalytic activities of Co-doped ZIF-8 (Co-ZIF-8) and Fe₃O₄/MCC/Co-ZIF-8 were evaluated for the photodegradation of methylene blue (MB) under visible light irradiation from a 20 W LED source. Co-ZIF-8 showed considerably higher photocatalytic activity than pure ZIF-8, confirming the success of the doping strategy. Both Co20%-ZIF-8 and Fe₃O₄/MCC/Co20%-ZIF-8 exhibited similar and remarkable photocatalytic activity under visible light (achieving 97% MB removal). The mechanism of photodegradation of MB by Fe₃O₄/MCC/Co20%-ZIF-8 was studied, revealing a first-order degradation kinetics (k = 13.78 × 10^-3 min^-1), with peroxide and hole species as the predominant active reagents. The magnetic composite successfully displayed recyclability and reusability over multiple cycles with negligible reduction in MB photodegradation efficiency.