Metal-organic frameworks (MOFs) and related other advanced porous materials for sequestration of heavy metal-based toxic oxo-pollutants from water

Abstract

In recent years, environmental pollution and its effects have demanded attention from all over the world. In this context, water pollution has been regarded as one of the biggest threats to all living forms among all types of pollution in recent years, and things are forecasted to get worse if remediating steps are not adopted soon. Water recycling has gained importance in the twenty-first century as more areas of the world experience a water crisis. Given this, ground-water pollution by heavy metal-based toxic oxo-pollutants such as CrO₄²⁻, Cr₂O₇²⁻, AsO₄³⁻, SeO₃²⁻, SeO₄²⁻, TcO₄⁻, ReO₄⁻ etc. have been becoming rapidly growing global concerns and pose a major risk to both human health and the environment. These hazardous and persistent chemicals have been designated as priority pollutants by the US Environmental Protection Agency (EPA) due to their extreme toxicity following bioaccumulation. Therefore, it is crucial to get rid of them from contaminated water in an efficient manner. In this regard, now a days, Advanced Functional Porous Materials (AFPMs) such as metal-organic frameworks (MOFs), porous organic polymers (POPs), covalent organic frameworks (COFs), and porous hybrid composite have drawn significant attention from researchers looking into wastewater treatment owing to their advantages of tunable porosity, high surface area, and an abundance of functional groups over traditional adsorbents. This review provides an overview of the latest advancements in Advanced Functional Porous Materials, including MOFs and related porous materials, used as effective adsorbents to remove harmful oxoanions derived from heavy metals from contaminated water. Additionally, the review suggests practical solutions for ensuring the safety and cleanliness of drinking water. Furthermore, their adsorption mechanisms are discussed which may enable better designing of new MOFs/AFPMs-based adsorbents with superior performance for future study as well as for understanding the adsorption process between MOFs/AFPMs and heavy metal oxoanions contaminants. Lastly, in order to fully comprehend the developing prospects for the future, the potential and challenges of MOFs/AFPMs were thoroughly discussed.