Surface hybridization of π-conjugate structure cyclized polyacrylonitrile and radial microsphere shaped TiO2 for reducing U(VI) to U(IV).

It is still a challenge to obtain uranium (U) adsorbents with high selectivity, excellent cycle stability and excellent performance through design and synthesis. In this paper, the TiO2/CPAN-AO catalyst was prepared by the hydrothermal method combined with high temperature cyclization dehydrogenation. TiO2/CPAN-AO has excellent photocatalytic properties, which can reduce U(VI) to U(IV) quickly and selectively. The generated Z-type heterojunction promotes the reduction ability of photogenerated electrons, and obtains great selectivity to UO22+ (Uranyl ions) through the AO group. TiO2/CPAN-AO with π-electron conjugated structure broadens the spectral range through surface hybridization and prolongs the lifetime of photo-generated charges. Under the induction of light, the uranium extraction capacity of TiO2/CPAN-AO after 5 h of irradiation is about 2.38 g/g. TiO2/CPAN-AO is a catalyst with enhanced adsorption capacity, making it possible to extract uranium from large-scale natural seawater in the future.