Potassium niobate nanolamina: A promising adsorbent for entrapment of radioactive cations from water

Processing and managing radioactive waste is a great challenge worldwide as it is extremely difficult and costly; the radioactive species, cations or anions, leaked into the environment are a serious threat to the health of present and future generations. We report layered potassium niobate (K₄Nb₆O₁₇) nanolamina as adsorbent to remove toxic Sr²⁺, Ba²⁺ and Cs⁺ cations from wastewater. The results show that K₄Nb₆O₁₇ nanolamina can permanently confine the toxic cations within the interlayer spacing via a considerable deformation of the metastable layered structure during the ion exchange process. At the same time, the nanolaminar adsorbent exhibits prompt adsorption kinetics, high adsorption capacity and selectivity, and superior acid resistance. These merits make it be a promising material as ion exchanger for the removal of radioactive cations from wastewater.