Photodegradation of MC-LR using a novel Au-decorated Ni metal-organic framework (Au/Ni-MOF)

Stephanie Stoll; Wei Zhang; Yang Yang; Kyungik Gil; Keugtae Kim; Woo Hyoung Lee

doi:10.1016/j.chemosphere.2023.140404

Photodegradation of MC-LR using a novel Au-decorated Ni metal-organic framework (Au/Ni-MOF)

Chemosphere. 2023 Dec:344:140404. doi: 10.1016/j.chemosphere.2023.140404. Epub 2023 Oct 10.

Authors

Stephanie Stoll¹, Wei Zhang², Yang Yang³, Kyungik Gil⁴, Keugtae Kim⁵, Woo Hyoung Lee⁶

Affiliations

¹ Department of Civil, Environmental, and Construction Engineering, University of Central Florida, Orlando, FL, 32816, United States. Electronic address: Stephanie.Stoll@ucf.edu.
² NanoScience Technology Center, Department of Materials Science and Engineering, University of Central Florida, Orlando, FL, 32826, United States. Electronic address: wei.zhang5@ucf.edu.
³ NanoScience Technology Center, Department of Materials Science and Engineering, University of Central Florida, Orlando, FL, 32826, United States; Department of Chemistry, Renewable Energy and Chemical Transformation Cluster, The Stephen W. Hawking Center for Microgravity Research and Education, University of Central Florida, Orlando, FL, 32826, United States. Electronic address: Yang.Yang@ucf.edu.
⁴ Department of Civil Engineering, Seoul National University of Science and Technology, Nowon-gu, Seoul, 01811, South Korea. Electronic address: kgil@seoultech.ac.kr.
⁵ Department of Biological and Environmental Science, Dongguk University, 32 Dongguk-ro, Ilsandong-gu, Goyang, Gyeonggi-do, Republic of Korea. Electronic address: kkt38@dongguk.edu.
⁶ Department of Civil, Environmental, and Construction Engineering, University of Central Florida, Orlando, FL, 32816, United States. Electronic address: woohyoung.lee@ucf.edu.

PMID: 37827467
DOI: 10.1016/j.chemosphere.2023.140404

Abstract

Microcystins (MCs) are toxins produced by cyanobacteria commonly found in harmful algal blooms (HAB) occurring in many surface waters. Conventional methods for removing MC-LR such as membrane filtration and activated carbon are only phase change removal methods and are often expensive in operation and maintenance. It is urgent to develop a rapid, easy-to-use, and cost-effective method for the degradation of MC-LR. In this study, a novel Au-decorated Ni-metal-organic framework (Au/Ni-MOF) was newly developed on a hydrophilic carbon fiber paper (2 cm × 2 cm) using an air spraying method. The Au/Ni-MOF was then applied for the photodegradation of MC-LR in water under UV-Vis. The addition of Au onto the surface of the Ni-MOF resulted in a nearly fivefold enhancement in the reaction rate coefficient (k), reaching a value of 0.0599 min^-1 for the photodegradation of MC-LR (initial concentration of 20 ppb). It was found that 94.2% of MC-LR removal was attributed to photodegradation, with the remaining 5.8% from adsorption. The rate coefficient of 20 ppb of MC-LR in the surface water sample (pH 6.0) was 0.06 min^-1 likely due to the presence of other contaminates including scavenger agents within the sample which inhibits the degradation reaction of the MC-LR. Overall, this study demonstrated the potential for the novel Au/Ni-MOF to effectively reduce the concentration of the MC-LR toxin in the contaminated water.

Keywords: Metal-organic framework (MOF); Microcystins; Photocatalyst; Sunlight; Visible light.

MeSH terms

Cyanobacteria*
Metal-Organic Frameworks*
Microcystins
Photolysis
Water
Water Purification* / methods

Substances

Metal-Organic Frameworks
Microcystins
Water