Solvothermally and non-solvthermally fabricated covalent organic frameworks (COFs) for eco-friendly remediation of radiocontaminants in aquatic environments : a review

Abstract

Soil and water are the most essential nonliving natural gift for all essential and nonessential actions in life, without which the earth inhabitants cannot exist because all living things rely on these gifts for their survival since time began. Thus, jealous conservation of these two natural resources is very crucial given to the massive global growth of industries and the enormous usage of nuclear power plant, nuclear warheads, radioactive medical facilities and radioisotopes in agriculture which has led to the release of silent killer ions known as radiocontaminants into the environment. Owing to the global socio-ecological threat pose by these radionuclei ions, exploring highly porous functional materials like covalent organic frameworks (COFs) has recently aroused interest for the elimination of these notorious ions because of their intriguing properties as per pre-designable configuration/framework, adjustable morphology, adaptable functionality, eco-benignness, high stability, surface area, adsorption capacity and efficiency, and which put them at the forefront than other materials. This review therefore discusses the eco-fundamental effects of radio-contaminants to life, and the holistic application of COFs for the removal of these silent killer radiocontaminants in water with special emphasis on the pragmatic remediation mechanism, adsorption capacity, and regenerability and reusability of spent COFs. This study revealed that the lowest number of reusability rounds was 4 cycles, and the highest was 9 cycles, while the highest COF radiocontaminant removal efficacy after nth cycle was >99. In the end, this work also presented some insightful knowledge gaps and initiatives future research hotspots that can be beneficial to broad of readership and researchers.