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Our photocatalyst possesses homo/heterojunction structure, which consists of hexagonal CdS, cubic CdS and Prussian blue. This design of homo/heterojunction structure not only achieves ideal energy band structure, which makes for stable and rapid separation of photogenerated electrons-holes, but also improves stability of photocatalyst in various extreme circumstances. Therefore, the photocatalytic activity is significantly enhanced. [Display omitted] • The homo/heterojunctions structures were designed via one-pot kinetic regulation. • The rational energy band distribution enhances photocatalytic activity. • The strong chelation between cyanogroups and Cd2+ improve the stability. • The photocatalysts possess excellent reusability. Photoreduction of soluble U(VI) to insoluble U(IV) by CdS-based catalysts shows great potential in remediating radioactive wastewater in terms of environmental friendliness and desirable bandgap as well as the availability of CdS, but is still limited by undesirable efficiency and stability from photogenerated carrier recombination and photocorrosion. Herein, we have elegantly designed tailor-made CdS@Prussian blue with homo/heterojunctions via one-pot kinetic regulation. The key to such a structure is to leverage the outstanding binding affinity between cyanogroups of Prussian blue and Cd2+ to create diversity of local precursor concentration differences. With such unique structure and rational energy band distribution, our photocatalysts demonstrate an unprecedented U(VI) removal efficiency as high as 2.5 times that of the pristine CdS. More importantly, the strong chelation between cyanogroups and Cd2+ endows our catalysts with extremely excellent stability compared with other state-of-the-art composite photocatalysts. This work provides a facile and universal inspiration for homo/heterojunction engineering of high-performance photocatalysts for photoreduction of uranium. [ABSTRACT FROM AUTHOR]

Electric-field driven uranium extraction from seawater has been proved to greatly enhance the performances of various adsorbents via gathering uranyl ions at the surfaces, but high-concentration interfering cations would also be enriched which generates shielding effects to reduce adsorption capacity. To address this issue, we have fabricated nanofiltration membranes with sieving-adsorption properties by choosing polyamidoxime (PAO) as substrates and polyamide as skin layers. On the one hand, the polyamide skin layers fabricated by interfacial polymerization could effectively separate uranyl ions from other metal ions according to the size-sieving effect since the size of uranyl ions is much larger than most interfering cations. The results demonstrated that the nanofiltration membranes could nearly 100 % reject uranyl ions while the rejections of other metal ions below 30 %. On the other hand, the rejected uranyl ions would be enriched at the surfaces of PAO substrates and followed by adsorption. The increased uranium concentrations are beneficial for both adsorption capacity as well as adsorption rate. Therefore, the adsorption capacity increased by 30 % compared with the pristine PAO adsorbents. This work not only provides a new strategy for the design of high-performance adsorbents, but also could promote the engineering process of uranium extraction from seawater which has an important scientific significance and application value. [Display omitted] • Nanofiltration membrane with sieving and adsorption properties is prepared. • Electric fields are beneficial for the gathering of uranium at membrane surfaces. • The NF membranes could separate uranium from interfering metal ions. • The adsorption capacity of NF membrane increased by 154 % compared with the pristine PAO adsorbent. [ABSTRACT FROM AUTHOR]