An ideal porous adsorbent toward uranium with not only large adsorption capacity and high selectivity but also broad applicability even under rigorous conditions is highly desirable but still extremely scarce. In this work, a porous adsorbent, namely [NH₄]⁺[COF‐SO₃⁻], prepared by ammoniating a SO₃H‐decorated covalent organic framework (COF) enables remarkable performance for uranium extraction. Relative to the pristine SO₃H‐decorated COF (COF‐SO₃H) with uranium adsorption capacity of 360 mg g⁻¹, the ammoniated counterpart of [NH₄]⁺[COF‐SO₃⁻] affords ultrahigh uranium uptake up to 851 mg g⁻¹, creating a 2.4‐fold enhancement. Such a value is the highest among all reported porous adsorbents for uranium. Most importantly, a large distribution coefficient, K_d^U, up to 9.8 × 10⁶ mL g⁻¹ is observed, implying extremely strong affinity toward uranium. Consequently, [NH₄]⁺[COF‐SO₃⁻] affords highly selective adsorption of uranium over a broad range of metal ions such as S_U/Cs = 821, S_U/Na = 277, and S_U/Sr = 124, making it as effective uranium adsorbent from seawater, resulting in amazing uranium adsorption capacity of 17.8 mg g⁻¹. Moreover, its excellent chemostability also make it an effective uranium adsorbent even under rigorous conditions (pH = 1, 8, and 3 m acidity).

Separation of C₂H₄ from C₂H₄/C₂H₂/C₂H₆ mixture with high working capacity is still a challenging task. Herein, we deliberately design a Th-metal-organic framework (MOF) for highly efficient separation of C₂H₄ from a binary C₂H₆/C₂H₄ and ternary C₂H₄/C₂H₂/C₂H₆ mixture. The synthesized MOF Azole-Th-1 shows a UiO-66-type structure with fcu topology built on a Th₆ secondary building unit and a tetrazole-based linker. Such noticeable structure, is connected by a N,O-donor ligand with high chemical stability. At 100 kPa and 298 K Azole-Th-1 performs excellent separation of C₂H₄ (purity > 99.9%) from not only a binary C₂H₆/C₂H₄ (1:9, v/v) mixture but also a ternary mixture of C₂H₆/C₂H₂/C₂H₄ (9:1:90, v/v/v), and the corresponding working capacity can reach up to 1.13 and 1.34 mmol g⁻¹, respectively. The separation mechanism, as unveiled by the density functional theory calculation, is due to a stronger van der Waals interaction between ethane and the MOF skeleton.

A facile method by means of MOF materials is used for the first time for the extraction of U(vi) ions from seawater, showing a significant extraction efficiency of 0.53 mg g⁻¹.

Mercury (Hg²⁺), even an ultra-low-concentration amount in water, presents a serious environmental concern. Thus, the removal, especially Hg(II) content at the ultratrace levels (ppb), from water is still challenging. In this work, without any pretreatment, anovel MOF material can act as a high-capacity and collectable adsorbent for the removal of Hg(II) from water, especially for ultratrace Hg²⁺ ions in the ppb magnitude, mainly due to a combined effect from the pore walls functionalized by free-standing, accessible acylamide and hydroxyl units.