A Robust Anionic Metal–Organic Framework for Efficient Capture of Rubidium: Performance and Mechanism Study

High-efficiency adsorbents for rubidium ions (Rb+) are still being actively researched and developed to meet the growing demands in various industries. Herein, the cost-effective ellagic acids were selected as organic ligands to assemble with bismuth (Bi) and zirconium (Zr) metal clusters to prepare SU-101 and SU-102. Among the two samples, abundant cationic ions DMA (N,N’-dimethylacetamide) are balanced in the anionic skeleton of SU-102. Benefiting from the smooth channels and these abundant exchangeable ion sites in the 1D channel wall, SU-102 displays a high Rb+ adsorption capacity of 183.6 mg g–1. The powder-state SU-102 was successfully shaped to SU-102/PAN beads, and the dynamic Rb+ adsorption capacity can reach 110 mg g–1. Notably, the SU-102/PAN composite demonstrates significant superiority compared to powder adsorbents, with a particular emphasis on its adsorption capacity and notably improved recyclability. Eventually, this work offers guidance for the development of a high-performance adsorbent for Rb+ capture.