LAUSR

Radiocesium remediation is desirable for ecological protection, human health and sustainable development of nuclear energy. Effective capture of Cs + from acidic solutions is still challenging, mainly due to the low stability of the adsorbing materials and the competitive adsorption of protons. Herein, the rapid and highly selective capture of Cs + from strongly acidic solutions is achieved by a robust K + -directed layered metal sulfide KInSnS 4 (InSnS-1) that exhibits excellent acid and radiation resistance. InSnS-1 possesses high adsorption capacity for Cs + and can serve as the stationary phase in ion exchange columns to effectively remove Cs + from neutral and acidic solutions. The adsorption of Cs + and H 3 O + is monitored by single-crystal structure analysis, and thus the underlying mechanism of selective Cs + capture from acidic solutions is elucidated at the molecular level. The removal of radiocesium from acidic solutions is challenging. Here, the authors report the rapid and highly selective capture of cesium(I) from strongly acidic solutions by a robust layered metal sulfide.