An initial demonstration of hierarchically porous niobium alkylphosphonates coordination polymers as potent radioanalytical separation materials.

•The rare occurrence of niobium alkylphosphonates as radionuclide scavengers was initiated.•The hierarchically porous features and inherent phosphonate functionality were explored.•The competitive radionuclide sequestration was performed in acidic cocktail surrogates.•The distinctive uptake profiles could be utilized for facile radioanalytical separation.