Radiation Controllable Synthesis of Robust Covalent Organic Framework Conjugates for Efficient Dynamic Column Extraction of 99TcO4-

Anion-scavenging materials tailored for (TcO4)-Tc-99 trapping are urgently needed for both nuclear-related environmental remediation and management of spent nuclear fuel. For the first time, we report here an ultra-robust imidazolium-decorated covalent organic framework (COF) conjugate fabricated by an ionizing radiation strategy, for efficient capture of (TcO4)-Tc-99. The charged imidazolium moieties are controllably anchored into the channel of the COF by simply adjusting the gamma-ray dose, thereby leading to tunable ReO4 uptake up to 952 mg g(-1) with high selectivity and fast kinetics . More importantly, the high porosity and ultra-robust nanofiber structure of the COFs make them ideal packing materials for dynamic column experiments. >99.98% ReO4/TcO4 can be efficiently separated and re-collected, even after four adsorption. desorption cycles, ranking a new record of the elimination rate for ReO4 adsorption. The performance of these materials suggests attractive opportunities in practical applications for TcO4 removal from the environment and nuclear waste.