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[Display omitted] The excessive CO 2 emission has gained global attentions due to its potential effects on climate change, plant nutrition deterioration, and human health and safety. Metal-organic frameworks (MOFs) featured with high specific surface area, adjustable pore size, and tailorable morphology have been widely applied for CO 2 capture. However, some drawbacks of poor mechanical stability and uneven distribution of mesopores limit their further applications. Herein, we demonstrate a one-step synthesis of bimetallic center framework (OSSBCF) and pore reconstruction (PRC) strategy to prepare the hierarchical porous Zn/Co-ZIF@ANF aerogels. This unique design achieves the construction of efficient gas transfer channels and creates massive micropores with abundant Lewis basic adsorption sites. Benefiting from theses merits, the bimetallic Zn/Co-ZIF@ANF aerogels demonstrate high MOFs loading mass of 47.51 wt%, high specific surface area of 686.39 m2g−1, and large porosity of 99.31 %. Moreover, the bimetallic Zn/Co-ZIF@ANF aerogels exhibit an enhanced CO 2 adsorption capacity of 5.99 mmol/g and CO 2 /N 2 adsorption selectivity of 35 at 25 °C and 1 bar. The CO 2 capacity of bimetallic Zn/Co-ZIF@ANF aerogels keep up to 95.19 % after ten cycles of CO 2 adsorption, indicating the excellent long-term recycle stability. Therefore, this study provides a promising strategy to engineer hierarchical porous bimetallic MOF aerogels toward practical CO 2 capture. [ABSTRACT FROM AUTHOR]

[Display omitted] Fabricating a high-performance adsorbent as a desirable candidate for removing Pb2+ from aqueous water remains a challenge. Aramid nanofibers (ANFs) are promising building blocks that have realized multifunctional applications due to their intrinsic mechanical and chemical stability. Herein, an in situ loading strategy for preparing nanofiber composite aerogel was proposed by assembling ANFs into a 3D aerogel and applying it as host media for the in situ polymerization of pyrrole followed by facile redox reaction between the polypyrrole (PPy) and MnO 4 –1 to load manganese dioxide (MnO 2). The idea was to fully exploit the structural advantages of ultra-low bulk density, large specific surface area, and high porosity of ANFs, and the possible chemical adsorption characteristics of MnO 2 on the basis of ion exchange reaction. The adsorption capacity of 3D ANF/MnO 2 composite aerogel was as large as 554.36 mg/g for Pb2+. The adsorption mechanism based on an exchange reaction between Pb2+ and protons on the surface of MnO 2 was also investigated. The desorption results showed that the adsorption performance could remain up to 90% after five times of usage. In conclusion, this research provides promising insights into the preparation of high-performance lead adsorbent for water treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • ZIF-67 was in situ assembled onto ANF aerogel to get 3D monolith adsorbent. • ANF/ZIF-67 aerogel showed stable and competitive structural features. • ANF/ZIF-67 aerogel demonstrated high adsorption capacity for Cu2+ and Cr6+. • ANF/ZIF-67 aerogel displayed excellent adsorption capacity for CV and MO. • The adsorption capacity maintained up to 80% after five times of usage. The fabrication of a high-efficiency adsorbent, as a promising candidate for removing metal ions and organic dyes from aqueous solution, is a research hotspot but remains challenging. Aramid nanofibers (ANFs) are emerging building blocks that have realized multifunctional applications in various fields because of their intrinsic mechanical and chemical stability. In this research, three-dimensional (3D) ANF aerogel was assembled and applied in for in situ assembly of zeolitic imidazole framework-67 (ZIF-67). The aim, was to fully exploit the structural advantages of this composite's ultra-low bulk density, large specific surface area, and high porosity, as well as provide more available adsorption sites by ZIF-67 polyhedrons, to facilitate pollutant adsorption from waste water. The prepared 3D ANF/ZIF-67 composite aerogel possessed favorable adsorption performance for heavy metal ions (250.95 and 183.29 mg/g for Cu2+ and Cr6+, respectively) and organic dyes (199.36 and 65.98 mg/g for CV and MO, respectively), greatly exceeding that of the corresponding 3D ANF aerogel. Desorption experiments further demonstrated that up to 80% adsorption performance for heavy metal ions and organic dyes could be maintained after five times of usage. Hence, this research can provide new insights into the preparation of highly efficient adsorbents for water treatment. [ABSTRACT FROM AUTHOR]