“…The reduction of soluble uranyl ions to U(IV) precipitation followed by solid–liquid separation is an effective strategy for U removal from aqueous solutions. , A series of reduction methods, such as chemical reagent reduction, reductive solid materials, electrochemical reduction, , microbial-assisted reduction, and photocatalytic reduction have been explored. Heterogeneous photocatalytic reduction is considered to be an environmentally friendly and economic method among them, especially the visible light-driven photocatalytic reduction. − However, several shortcomings of traditional photocatalysts limit their further applications, for example, the narrow band gap of TiO 2 and g-C 3 N 4 resulted in the weak utilization of visible light, high power Hg or Xe lamps are required in photocatalysis; otherwise, it usually leads to slow catalytic reduction rate U(VI). − Efficient photocatalytic reduction of uranyl by COF materials has also been reported. COF DHBD-TMT (DHBD, 2,5-dihydroxy-1,4-benzenedicarboxaldehyde; TMT, 2,4,6-trimethyl-1,3,5-triazine) possess hydroquinone and highly planar conjugated triazine units on the skeleton, which enhances the π-electron delocalization and decreases the optical band gap, thereby COF DHBD-TMT has good light utilization ability and could reach adsorption and reduction equilibrium of 500 ppm U within 200 min, but a high power 300 W xenon lamp is needed …”