Decorating metal organic framework on nickel foam for efficient Cu2+ removal based on adsorption and electrochemistry.

The removal of heavy metal ions in wastewater has a great significance to human health and environment protection. Metal organic framework possesses high surface area, rich porosity, tunable pore size and abundant active sites. However, the intrinsic aggregation and fragility of MOF nanoparticles make its poor adsorption and undesirable reusage. Herein, a facile and unique hot-pressing method is adopted to decorate the MOF nanoparticles on nickel foam (ZIF-8/NF), which simultaneously serves as self-supporting substrate of ZIF-8 nanoparticles and electrode of a self-powered multifunctional purification system. In adsorption, the ZIF-8/NF composite presents high Cu2+ removal rate of 49.5% with the concentration of 10 mg/100 ml. More importantly, integrating with electrochemistry, the Cu2+ removal rate of the ZIF-8/NF composite reaches 54.7% in 5 min. The superior performance is attributed to the comprehensive effects of ion exchange, chemical bonding and physical adsorption. Moreover, the low-cost, fast and scalable preparation contributes to commercially fabricate MOF nanoparticles on self-supported substrate to treat wastewater with high efficiency and good recyclability.

Electrospun ZIF-derived cavity porous carbon nanofibers as a freestanding cathode for lithium-oxygen batteries with ultralow overpotential.

Construction of an efficient electrocatalyst for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) with low overpotential and cycling stability for lithium-oxygen batteries still remains a puzzling challenge. Herein, we propose a scalable approach to integrate ZIF derivatives into cavity porous carbon nanofibers (CPCNFs) via an electrospinning technique and thermal treatment (Zn/CoNC@CPCNFs). The ultralong interconnected nanofiber matrix is beneficial, and the developed Zn/CoNC@CPCNFs catalyst with excellent flexibility can be utilized as a free-standing electrode based on an air-cathode. Moreover, this confinement strategy ensures the dispersion of Co-based species and abundant porosity structure, which contributes to the transport and adsorption of oxygen and exposes more Co-N coordination catalytic centers, as a result of a drastically ultralow voltage gap. Consequently, a cell based on a Zn/CoNC@CPCNF electrode presents remarkably decreased charge-discharge polarization (0.36 V), a high initial discharge capacity with an ultra-low overpotential of 0.59 V, and long-term cyclability with a cut-off capacity of 0.2 mA h cm-2 at 0.02 mA cm-2. We hope that our protocol will offer instruction for the design and application of oxygen electrocatalysts for energy conversion and storage.

UiO-66-NH2 Fabrics: Role of Trifluoroacetic Acid as a Modulator on MOF Uniform Coating on Electrospun Nanofibers and Efficient Decontamination of Chemical Warfare Agent Simulants.

Protective fabrics with air-permeable and flexible features are crucial for practical application in the detoxification of chemical warfare agents (CWAs). Zr-based metal-organic frameworks (Zr-MOFs) are desirable to exhibit outstanding degradation toward CWAs. However, generally, MOFs with powders cannot afford the utilization as a protective layer directly; meanwhile, it is still a puzzling challenge to integrate MOFs with textiles efficiently. Herein, we develop a scalable and controllable strategy to fabricate UiO-66-NH2 on electrospun polyacrylonitrile nanofibers (UiO-66-NH2 fabrics) firmly and uniformly to capture and catalyze 2-chloroethyl ethyl sulfide (CEES) effectively for self-detoxification. The obtained UiO-66-NH2 fabrics are greatly capable of specific surface area, ample porosity, excellent crystallinity, and abundant catalytic active sites. Consequently, CEES can be removed efficiently up to 97.7% after 48 h by reaction and adsorption. The degradation products mainly including ethyl-2-hydroxyethyl sulfide, ether, bis[2-(ethylthio)ethyl], and 2-(2-(ethylthio)ethylamino) terephthalic acid are detected. Moreover, the obtained nanofibrous fabrics possess air-permeable, washable, and flexible as well as lightweight merits, totally ensuring their promising engineering applications for protective clothing.

Heavy metal elimination based on metal organic framework highly loaded on flexible nanofibers.

Efficient adsorbents for removal heavy metals are extensively urgent in modern society. Metal-organic frameworks (MOFs) with abundant porosity and tunable structure make it potential to access the advantages of high permeability and adsorbability in water pollutant control. However, MOFs nanoparticles inconvenient to recycle in solution hinder its application in water pollutant treatment. Herein, we report an in-situ growth and large-scalable manufacturing method to fabricate ZIF-8 nanoparticles on electrospun polyacrylonitrile (PAN) nanofibers membrane (ZIF-8/PAN NF) by hot pressing. Consequently, the prepared ZIF-8/PAN NF possesses high loading, uniform dispersion and large-scalable area as well as good flexibility. The fabricated ZIF-8/PAN NF exhibits excellent performance with fast flux (12,000 L/(m2h)) and high filtration efficiency (96.5%) for Cu2+ in dynamic adsorption. Additionally, adsorption and electrochemistry are introduced simultaneously. The Cu2+ removal rate of ZIF-8/PAN NF reaches 34.1% in 4 min with combination of adsorption and electrochemistry. While it is 29.2% for Cu2+ elimination in adsorption. Given the outstanding performance and easy manufacture, this study might bring MOFs powder to eliminate water pollution into practical application.