Speeding up the selective extraction of uranium through in situ formed nano-pockets

Abstract

Seeking an efficient sorbent for capturing uranium from seawater is the key to ensure the sustainable development of nuclear energy. Herein, electron-rich covalent polymer aerogels (ECP gels) with an independent self-supporting structure were facilely developed by a precipitation polycondensation method. The electron-rich ligand 3,3′-diaminobenzidine (DAB) regulates electron arrangement around PN and enhances its binding capacity as a Lewis basic site. The ECP gels reached equilibrium in 2 min and exhibited a groundbreaking adsorption rate of 203.01 mg g⁻¹ min⁻¹. EXAFS analysis and DFT calculations revealed that the PN and in situ generated rich accessible phosphorus hydroxyl group assembled into nano-pockets to provide an electronic-rich environment for uranium selective adsorption. Exposed in natural seawater, the ECP gels reached an outstanding uranium uptake capacity of 10.43 mg g⁻¹. The novel ECP gels have great potential for efficient and rapid extraction of uranium from seawater.