Industrial utilization of nuclear resources greatly depends on the effective treatment of nuclear waste. The efficient removal of radioactive nuclides from liquid effluents by using different adsorbents has thus become crucial. Herein, for the first time, two-dimensional transition metal carbides (MXenes) are investigated as scavengers of cesium (Cs⁺) from contaminated water. Due to the combined advantages of the layered structure and the presence of heterogeneous sites (hydroxyl, oxygen and fluorine groups), the adsorbent reached the steady state within 1 min with the maximum Cs⁺ adsorption capacity of 25.4 mg g⁻¹ at room temperature. The kinetics studies of the Cs⁺ scavenging process demonstrated that the adsorption of Cs⁺ followed the pseudo-second-order model whereas the adsorption equilibrium data obeyed the Freundlich model. Thermodynamic studies revealed that the adsorption process was endothermic. The adsorbent showed an excellent Cs⁺ removal efficiency in neutral to slightly alkaline solutions. Moreover, it can retain Cs⁺ even in the presence of a high concentration of competing cations (Li⁺, Na⁺, K⁺, Mg²⁺ and Sr²⁺). The Cs⁺ loaded adsorbent was regenerated with a 0.2 M HCl solution and reused at least five times for over 91% removal of contaminants.

Over the years, manganese dioxide (MnO ₂ ) and its different allotropes have gained significant research attention in the field of wastewater treatment because of their exciting physicochemical properties.

As a result of extensive research efforts by several research groups, magnetite-based materials have gained enormous attention in diverse fields including biomedicine, catalysis, energy and data storage devices, magnetic resonance imaging, and environmental remediation. Owing to their low production cost, ease of modification, biocompatibility, and superparamagnetism, the use of these materials for the abatement of environmental toxicants has been increasing continuously. Here we focus on the recent advances in the use of magnetite-based adsorbents for removal of radionuclides (such as ¹³⁷Cs(I), ¹⁵⁵Eu(III), ⁹⁰Sr(II), ²³⁸U(VI), etc.) from diverse aqueous phases. This review summarizes the preparation and surface modification of magnetite-based adsorbents, their physicochemical properties, adsorption behavior and mechanism, and diverse conventional and recent environmental technological options for the treatment of water contaminated with radionuclides. In addition, case studies for the removal of radionuclides from actual contaminated sites are discussed, and finally the optimization of magnetite-based remedial solutions is presented for practical application.

MXenes, since their discovery in 2011, have garnered significant research attention for a variety of applications due to their exciting physico-chemical properties.