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The anionic uranyl-organic framework not only effectively adsorbs diquat herbicide through electrostatic and π-π stacking interactions, but also possesses semiconductor-like properties that allow for the harmless and complete removal of diquat by photocatalytic degradation. [Display omitted] • Synthesis of a novel light-sensitive three-dimensional uranyl-organic framework with anionic skeleton was achieved. • The compound can serve as both efficient absorbent and photocatalyst for the removal of diquat. • The adsorption and degradation removal ratio for diquat can reach 100%. • The compound can be regenerated and reused under light irradiation after adsorption of diquat. Adsorption and photocatalysis are generally considered an environmental friendliness and effective methods for eliminating organic pollutants. Developing bifunctional materials that integrate adsorption and photocatalysis can fully leverage the adsorption effect to increase the interaction between herbicides and photocatalysts, thus improving their photocatalytic degradation efficiency. To achieve the absorption and photocatalytic activity on contaminants, a light-sensitive three-dimensional uranyl-organic framework (UOF) named HNU-80 with an anionic skeleton was synthesized in this work. The charge characteristics of its electrostatic attraction with cations and the suitable band structure for producing reactive oxygen endow it with the potential for efficient adsorption and photocatalytic oxidation of the cationic diquat herbicide. The maximum adsorption capacity is up to 97.92 mg·g−1, and the adsorbed diquat could be completely degraded under light irradiation. In addition, the regenerated HNU-80 exhibits high reusability in subsequent adsorption cycle experiments. The adsorption mechanism is attributed to the electrostatic and π...π interaction between HNU-80 and diquat, while the photodegradation mechanism is due to the oxidation and decomposition of diquat by reactive oxygen species generated from the radiation of HNU-80. This work provides a promising candidate for the harmless treatment of organic pollutants, and the combination of photocatalytic property also promotes the regeneration of the UOF adsorbents for continued use. [ABSTRACT FROM AUTHOR]

[Display omitted] • The CNQDs/CN/CNTs photocatalyst was obtained by a microwave hydrothermal method. • The CNQDs/CN/CNTs has higher separation efficiency of photogenerated carriers. • CNQDs and CNTs together enhanced the photocatalytic performance of g-C 3 N 4. • The CNQDs/CN/CNTs generated 1109.388 μmol∙g−1∙h−1 hydrogen with QY of 52.08%. Utilizing solar energy to facilitate photocatalytic hydrogen production holds great promise in addressing the energy crisis. One material that shows tremendous potential in this field is two-dimensional graphitic carbon nitride (2D g-C 3 N 4). However, the fast recombination rate of photogenerated carriers and the limited specific surface area impede its photocatalytic activity. This research endeavors to address these limitations by developing a ternary composite photocatalyst, CNQDs/g-C 3 N 4 /CNTs, by employing the microwave hydrothermal method. g-C 3 N 4 was co-modified with zero-dimensional g-C 3 N 4 quantum dots (0D CNQDs) and one-dimensional carbon nanotubes (1D CNTs). Incorporating CNQDs and the g-C 3 N 4 interface facilitates the separation of photogenerated carriers, while the tubular channel of CNTs provides favorable conditions for transferring photogenerated electrons. Additionally, the introduction of CNQDs and CNTs significantly increases the specific surface area of the sample, thereby enhancing the number of reaction active sites available for the photocatalytic production of hydrogen. The hydrogen generation rate of the CNQDs/g-C 3 N 4 /CNTs is 1109.388 μmol⋅g−1⋅h−1, surpassing that of the single g-C 3 N 4 specimen by 3.62 times. The application of density functional theory (DFT) calculations reinforces the enhanced performance of the composite through the synergistic effect of CNQDs and CNTs. This effect optimizes the adsorption behavior of the active intermediate (H*) and reduces the Gibbs free energy ΔG(H*) associated with the photocatalytic hydrogen evolution reaction. [ABSTRACT FROM AUTHOR]

Utilizing in-situ hydrothermal synthesis, the integration of MIL-88A with self-made PVA sponge was achieved, forming MIL-88A/PVA composite, which demonstrates effective performance in degrading tetracycline antibiotics during water treatment. [Display omitted] • The MIL-88A/PVA sponge composite achieves a high removal rate within 4 min. • MIL-88A/PVA treats 2160 L wastewater in 24 h in fixed-bed column experiments. • The composite's bulk morphology is customized to meet specific industrial requirements. • This approach expands the application of MOF materials in antibiotic wastewater treatment through sulfate radical-advanced oxidation processes. MIL-88A is a metal–organic framework (MOF) material known for its excellent performance in advanced oxidation processes (AOPs). However, due to its powdery nature, MIL-88A may undergo loss during catalytic degradation in flowing solutions, making continuous degradation removal challenging. Herein, we report the synthesis of MIL-88A/PVA sponge composite material by the in-situ integration of MIL-88A with PVA sponge. The composite sponge exhibits excellent removal efficiency of tetracycline antibiotics under the conditions of sulfate radical-advanced oxidation processes (SR-AOPs), achieving a degradation rate exceeding 99.0% within 2 min. Additionally, through fixed-bed column experiments, 1 kg of MIL-88A/PVA can treat 2160 L of wastewater within 24 h, indicating promising industrial applicability. It's worth noting that this material can be customized into any desired block shape as needed. This work offers a highly promising solution for the application of MOF-based bulk-type catalysts in the treatment of antibiotic pollution using SR-AOPs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Confined growth of TIF-A1 in chitosan matrix was realized. • Composite beads show very high removal efficiency for trace lead. • The lead concentration after treatment meets the WHO guideline. • Great application potential in reclaimed water treatment is demonstrated. The removal of lead ions from water is a global concern due to the great damage to human health when they enter the human body through drinking water. Herein, metal-organic framework/chitosan composite beads for the adsorption of Pb(II) were prepared by the secondary growth method, which allowed the domain-limited growth of TIF-A1 (a tetrahedral imidazolate framework) in the porous matrix of chitosan. This material can remove trace Pb(II) from aqueous solution (100 ppb) with an efficiency of 99.95%, and the remaining Pb(II) content meets the international drinking water standards. Moreover, it exhibited good recoverability for at least five adsorption/desorption cycles. The adsorption mechanism can be ascribed to that Pb(II) ions chelate with the hydroxyl, carboxyl and amino groups in the adsorbent. This work offers a good adsorbent for the removal of trace Pb(II), which has potential applications in reclaimed water treatment. [ABSTRACT FROM AUTHOR]

• Ni(HBTC)(bipy) and Ni 2 (HBTC) 2 (bipy) 0.6 (dabco) 1.4 exhibit preferential adsorption of C 2 H 6 over C 2 H 4. • Ni(HBTC)(bipy) has high C 2 H 6 adsorption uptake of 6.6 mmol/g at 25 °C and 1 bar. • C 2 H 6 /C 2 H 4 selectivity of Ni(HBTC)(bipy) and Ni 2 (HBTC) 2 (bipy) 0.6 (dabco) 1.4 is 1.4–1.7 at 25 °C. Adsorptive separation is a promising alternative to the energy-intensive cryogenic distillation process for separating the ethane/ethylene (C 2 H 6 /C 2 H 4) mixtures. Herein, two pillared-layer metal-organic frameworks (MOFs), Ni(HBTC)(bipy) and Ni 2 (HBTC) 2 (bipy) 0.6 (dabco) 1.4 , are prepared as the C 2 H 6 -selective adsorbents for C 2 H 4 purification from C 2 H 6 /C 2 H 4 mixtures. The effect of the type of pillars on the framework structure, thermal and moisture stability, as well as the C 2 H 6 and C 2 H 4 adsorption propertiy, of the MOFs was studied. The use of the longer pillars (i.e. bipy versus dabco) to scafolld the Ni(HBTC) improved the pore size (5.5 Å versus 5.3 Å), specific surface area (1474 m2/g versus 1070 m2/g) and moisture stability in the relative humidity range of 0–90%, but compromised the thermal stability (267 °C versus 278 °C). Both MOFs were C 2 H 6 -selective, which was evidencd by the single component adsorption experiments using C 2 H 6 and C 2 H 4. The ideal adsorbed solution theory (IAST) selectivity for C 2 H 6 /C 2 H 4 mixtures (1:1 and 1:15, v / v) is in the range of 1.4–1.7 at 25–50 °C and 0–1 bar. The preferential adsorption towards C 2 H 6 over C 2 H 4 on both MOFs is then explained by the isosteric heat of adsorption. Additionally, Ni(HBTC)(bipy) also shows the best capacity of up to 6.6 mmol/g for C 2 H 6 adsorption in comparison with other C 2 H 6 -selective MOFs at 25 °C and 1 bar. Both MOFs showed the excellent recyclability, with the negligible reduction in the gas uptake observed during four cycles of adsorption/desorption tests. Besides, breakthrough experiments demonstrated that both MOFs can achieve efficient separation of an equimolar C 2 H 6 /C 2 H 4 mixture. The findings suggest that Ni(HBTC)(bipy) and Ni 2 (HBTC) 2 (bipy) 0.6 (dabco) 1.4 can be further considered as C 2 H 6 -trapping adsorbents for the C 2 H 6 /C 2 H 4 separation applications in practice. [ABSTRACT FROM AUTHOR]