Polymer-on-HOF: a new strategy for fabricating “armour-plated” HOFs to sequester radioactive anions

Abstract

The development of hydrogen-bonded organic frameworks (HOFs) faces significant constraints, primarily attributed to their fragile architectures and limited functionalization capabilities. To overcome these limitations, this work presents a new polymer-on-HOF strategy by covalently tethering armor-like polymers onto the surface of HOFs. The application of this approach not only bolsters the stability of HOFs, but also facilitates the customization of their functional expansion in radionuclide sequestration. The optimized HOF-polymer materials display extraordinary ability in radionuclide sequestration, achieving uptake of I⁻ (0.699 g g⁻¹), IO₃⁻ (0.285 g g⁻¹) and ReO₄⁻ (1.616 g g⁻¹, setting a world record), fast adsorption kinetics (~100% removal within 45 s), and exceptional regeneration capability (>30 cycles) under continuous flow conditions. These outstanding performances benefit from the internal porous channels and surface imidazolium polymer coatings of HOFs, as proved by density functional theory calculation and molecular dynamics simulations. This work paves the way for the rational design of HOF-based hybrid materials tailored to versatile applications.