Unconventional ion exchangers can achieve efficient removal of [UO], Cs, and Sr ions from complex aqueous solutions and are of great interest for environmental remediation. We report two new gallium thioantimonates, [MeNH][GaSbS]·HO (FJSM-GAS-1) and [EtNH][GaSbS]·HO (FJSM-GAS-2), which present excellent ion exchange properties for [UO], Cs, and Sr ions. They exhibit high ion exchange capacities for [UO], Cs, and Sr ions ( q = 196 mg/g, q = 164 mg/g, and q = 80 mg/g for FJSM-GAS-1, q = 144 mg/g for FJSM-GAS-2) and short equilibrium times for [UO] ion exchange (5 min for FJSM-GAS-1 and 15 min for FJSM-GAS-2, respectively). Both compounds display active ion exchange with [UO] in the pH range of 2.9-10.5. Moreover, the sulfide compounds could maintain high distribution coefficients K even in the presence of excess Na, Ca, and HCO. The distribution coefficient K of 6.06 × 10 mL/g exhibited by FJSM-GAS-1 is the highest among the reported U adsorbents. The [UO]-laden products can be recycled by conveniently eluting the uranium with a low-cost method. These advantages combined with facile synthesis, as well as β and γ radiation resistance, make FJSM-GAS-1 and FJSM-GAS-2 promising for selective separations in nuclear waste remediation.

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133Ba, 63Ni, and 60Co are hazardous to the ecosystem and human health. Their nonradioactive isotopes are also worthy of concern as toxic metal ions. Barium can be studied as a simulant of hazardous 226Ra because of their comparable ionic radii and similar ion exchange behaviors. Herein, we report that the layered metal sulfide (Me2NH2)1.33(Me3NH)0.67Sn3S7·1.25H2O (FJSM-SnS) exhibits excellent capture properties for Ba2+, Ni2+, and Co2+ with high capacities (q m Ba = 289.0 mg/g; q m Ni = 83.27 mg/g; and q m Co = 51.98 mg/g), fast kinetics (within 5 min), wide pH durability, and outstanding Ba2+ selectivity. FJSM-SnS exhibits high removal efficiencies (>99%) for these ions in ion-exchange column experiments. The material possesses radiation resistance with good structural and crystal stability; it survives highly acidic conditions. Our results point to a promising scavenger for Ba2+, Ni2+, and Co2+ and, by extension, the even more harmful 226Ra, which suggest that metal sulfide materials should be considered as effective scavengers for these ions from complex wastewater.