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The directed construction of productive adsorbents is essential to avoid damaging human health from the harmful radioactive and toxic U(VI)-containing wastewater. Herein, a sort of Zr-based metal organic framework (MOF) called PCN-222 was synthesized and oxime functionalized based on directed molecular structure design to synthesize an efficient adsorbent with antimicrobial activity, named PCN-222-OM, for recovering U(VI) from wastewater. PCN-222-OM unfolded splendid adsorption capacity (403.4 mg·g−1) at pH = 6.0 because of abundant holey structure and mighty chelation for oxime groups with U(VI) ions. PCN-222-OM also exhibited outstanding selectivity and reusability during the adsorption. The XPS spectra authenticated the -NH and oxime groups which revealed a momentous function. Concurrently, PCN-222-OM also possessed good antimicrobial activity, antibiofouling activity, and environmental safety; adequately decreased detrimental repercussions about bacteria and Halamphora on adsorption capacity; and met non-toxic and non-hazardous requirements for the application. The splendid antimicrobial activity and antibiofouling activity perhaps arose from the Zr6(μ3-O)4(μ3-OH)4(H2O)4(OH)4 clusters and rich functional groups within PCN-222-OM. Originally proposed PCN-222-OM was one potentially propitious material to recover U(VI) in wastewater on account of outstanding adsorption capacity, antimicrobial activity, antibiofouling activity, and environmental safety, meanwhile providing a newfangled conception on the construction of peculiar efficient adsorbent. [ABSTRACT FROM AUTHOR]

Due to the urgent demand for portable electronics, enormous research efforts are devoted for the development of flexible, wearable and lightweight supercapacitors. Herein, we report a cost‐effective chemical liquid process followed with a refluxing route to grow CC@CoMoO4‐Co(OH)2 nanosheets with Co‐based MOF as precursor. The resulting CC@CoMoO4‐Co(OH)2‐4 electrode delivers a significantly enhanced specific capacitance of 2028 F g−1 at 1 A g−1 and capacitance of 1581.8 F g−1 at 20 A g−1. Furthermore, the flexible all‐solid‐state asymmetric supercapacitor (CC@CoMoO4‐Co(OH)2//AC) is assembled, displays a high energy density of 61 Wh kg−1 at power density of 800 W kg−1, with an excellent cycle stability. These exceptional electrochemical performances could be ascribed to the unique structure and multi‐metal ion combination contributes to the ideal synergistic effects, which also signify that the potential application of CC@CoMoO4‐Co(OH)2 nansheets in high‐performance supercapacitors. [ABSTRACT FROM AUTHOR]

The design of hierarchical nanostructures with a controlled composition arrangement is a promising strategy to achieve high ion transport and enhanced charge storage for high-performance supercapacitor electrode development. Herein, we report a high-energy-density electrode based on CoP/Mo-NiCoP nanoplates array on carbon cloth templated by the metal-organic frameworks (MOFs). The unique hierarchical 3D structure provides an extremely large surface that enables excellent accessibility to the active surface sites, promoting electrochemical energy storage performance effectively. In addition, according to the density functional theory (DFT) calculation, Mo-doped in CoP/NiCoP nanoplates results in a desired electronic structure to enhance electronic transfer capability. As a result, the CoP/Mo-NiCoP electrode presents a high specific capacity of 892.6 C g−1 (248 mAh g−1) at the current density of 1 A g−1, as well as good rate capability (78.9% of capacity at 20 A g−1), and long-term cycling stability (82.6% retention after 10000 cycles at 4 A g−1). Furthermore, the assembled supercapacitor yielded a high energy density of 64.7 Wh kg−1 at 800 W kg−1 with an operating voltage of 1.6 V, outperforming most asymmetric supercapacitors. This work shows a promising hierarchical nanomaterial array for the development of high-performance flexible supercapacitors. [ABSTRACT FROM AUTHOR]

Electrode materials with a large internal surface area, tunable pore size, efficient transport of electrons and high ion-accessibility are highly desired in the development of advanced flexible supercapacitors. Recently, transition metal sulfides with rationally designed nanostructures have attracted considerable attention as electrode materials for supercapacitors. In this study, we report the synthesis of Zn 0.76 Co 0.24 S/NiCo 2 S 4 nanosheets grown on carbon cloth using a two-dimensional bimetallic Zn/Co zeolitic imidazolate framework (named as Zn/Co-ZIF-L) as a precursor through a simple and cost-effective chemical solution process. The ZIF-derived Zn 0.76 Co 0.24 S/NiCo 2 S 4 electrode nanosheets deliver an ultrahigh specific capacitance of 2674 F g−1 at 1 A g−1, a superior ratio performance and cycle stability. Furthermore, the as-fabricated Zn 0.76 Co 0.24 S/NiCo 2 S 4 //AC all-solid-state asymmetric supercapacitor (ASC) achieves a maximum energy density of 48.1 Wh kg−1 as well as a power density of 837 W kg−1, and a superior cycling performance of 91% retention after 5000 cycles. The detailed electrochemical kinetic analysis demonstrates that the total capacitance of Zn 0.76 Co 0.24 S/NiCo 2 S 4 is derived from its capacitive-effective charge storage mechanism. This ZIF-derived strategy provides a reasonable and simple way to synthesize transition metal sulfides as potential active materials for next-generation flexible supercapacitors. Image 1 • Zn/Co-based MOFs derived Zn 0.76 Co 0.24 S/NiCo 2 S 4 nanosheets were prepared successfully. • The Zn 0.76 Co 0.24 S/NiCo 2 S 4 electrode exhibited remarkable specific capacitance. • A flexible all-solid-state Zn 0.76 Co 0.24 S/NiCo 2 S 4 //AC ASC device was fabricated. • The enhanced property is due to the nanostructure, porosity and conductivity. [ABSTRACT FROM AUTHOR]

The extraction of U(VI) ions from aqueous solution was considered as a difficult task in the industry. In this study, a phosphate-modified metal-organic framework (PCN-224-HEDP) was designed and synthesized for efficient U(IV) adsorption via a common postsynthetic method of PCN-224 grafting hydroxyethylidene diphosphonic acid. [Display omitted] The extraction of U(VI) ions from aqueous solution was considered as a difficult task in the industry. In this study, a phosphate-modified metal-organic framework (PCN-224-HEDP) was designed and synthesized for efficient U(IV) adsorption via a common postsynthetic method of PCN-224 grafting hydroxyethylidene diphosphonic acid. The results of TEM, XPS, FT-IR, XRD and BET indicated the PCN-224-HEDP possessed regular cubic structure, high specific surface area and abundant phosphate functional groups. PCN-224-HEDP exhibited more excellent adsorption capacity for U (VI) than that of PCN-224. Besides, the adsorbent also exhibited great selectivity and recyclability of uranium adsorption. Furthermore, the uranium adsorption process of PCN-224-HEDP was in the control of chemical and monolayer adsorption, and the XPS spectra confirmed that the phosphate groups played a important role in the adsorption process. All results indicated that PCN-224-HEDP was an efficient adsorbent for U(VI) extraction from aqueous solutions. [ABSTRACT FROM AUTHOR]

Herein, a novel amidoxime functionalized metal organic framework (MOF)-based adsorbent named PCN-222-AO was obtained by grafting amidoxime groups on the surface of PCN-222 through amination, cyanylation and amidoximation modification reactions successively. The PCN-222-AO exhibited outstanding adsorption capacity (432.7 mg·g−1), selectivity and reusability in U(VI) adsorption at pH = 7.0, and showed superb adsorption performances in the simulated and real seawater. The XPS spectra and adsorption energy calculations confirmed the C N (H 2 TCPP), C=N-OH and -NH (2) groups served a vital role in the U(VI) adsorption process. PCN-222-AO illustrated excellent antibacterial property, anti-biofouling activity and environmental safety, which effectively reduced the negative impacts of bacteria (E. coli and S. aureus) and Halamphora upon the U(VI) adsorption capacity and complied with the requirements for non-toxicity and innocuousness in the adsorbent application. The excellent antibacterial property and anti-biofouling activity may be attributed to Zr 6 cluster and abundant functional groups in the PCN-222-AO. Undoubtedly, the molecular structure design and construction of effective adsorbents are crucial for the U(VI) resource recovery. As first reported in this study, PCN-222-AO is a promising adsorbent to recover U(VI) from seawater, providing a new idea about the molecular structure design and construction of novel high-efficiency adsorbent. [Display omitted] • Novel adsorbent named PCN-222-AO was synthesized based on molecular structure design. • PCN-222-AO exhibited distinguished antibacterial activity and recycling ability. • PCN-222-AO showed excellent U(VI) adsorption capacity, Q e reached 432.7 mg·g−1. • Mechanism was the co-effect of coordination and electrostatic interaction. • The adsorbent possessed great potential to efficiently recover U(VI) from seawater. [ABSTRACT FROM AUTHOR]

[Display omitted] • A porous Ag+ decorated PCN-222@graphene oxide-chitosan foam adsorbent was developed. • The adsorbent exhibited the excellent macrostructure and antibacterial property. • The adsorbent showed high U(VI) adsorption capacity, Q e reached 348.8 mg/g. • Mechanisms were coordination, electrostatic interaction and intraparticle diffusion. • The adsorbent possessed great potential to efficiently recover U(VI) from seawater. In this study, a 3D porous Ag+ decorated PCN-222 @ graphene oxide-chitosan foam adsorbent (APGC foam), which is grounded upon the growth of Ag+ decorated zirconium-metalloporphyrin metal–organic framework (PCN-222) on an EDTA-silane modified graphene oxide-chitosan foam substrate (EGC foam) for recovering U(VI) ions out of the seawater, was designed and synthesized with the in-situ growth and solvothermal method. The successfully synthesized APGC foam with excellent antibacterial property not only overcame the difficulty of powder adsorbents in practical application, but also reduced the negative impact of bacteria on the adsorption performance of porous material. The APGC foam showed excellent adsorption capacity (348.8 mg/g), selectivity and reusability of U(VI) adsorption at nearly seawater pH, and this also exhibited excellent adsorption performances in the seawater. The influence factors in the adsorption process were investigated by static and dynamic adsorption in different conditions. Moreover, the U(VI) adsorption mechanism of APGC foam was determined as the comprehensive effect of coordination, electrostatic interaction and intraparticle diffusion. All results indicated that APGC foam was an encouraging adsorbent to recover U(VI) out of the seawater. [ABSTRACT FROM AUTHOR]

In this study, a mesoporous PCN-222/GO-COOH adsorbent, based on the growth of a mesoporous zirconium-metalloporphyrin metal-organic framework (PCN-222) on the carboxylated graphene oxide (GO-COOH) to recover U(VI) from wastewater, was designed and prepared through solvothermal method and ultrasonication assisted stir technique. The U(VI) adsorption performance of the PCN-222/GO-COOH adsorbent was evaluated. The results indicated that the mesoporous PCN-222/GO-COOH adsorbent could effectively recover U(VI) and show an excellent adsorption capacity (426 mg/g), which was superior to those of GO-COOH and PCN-222 probably because the complexation and synergistic effect between GO-COOH and PCN-222 were facilitated by the ultrasonication assisted stir technique. And the PCN-222/GO-COOH adsorbent showed excellent reusability and selectivity for U(VI) adsorption, which also had outstanding adsorption performances in the complex wastewater. Furthermore, the chemical and monolayer adsorption dominated the U(VI) adsorption behavior of PCN-222/GO-COOH adsorbent. The excellent adsorption capacity, selectivity and reusability for U(VI) rendered PCN-222/GO-COOH composites as a promising adsorbent for recovering U(VI) from wastewater. [Display omitted] • A mesoporous PCN-222/GO-COOH adsorbent was successfully developed. • Ultrasonication assisted stir technique facilitated the adsorbent to form complex. • The adsorbent exhibited high U(VI) adsorption capacity, Q e reached 426 mg/g. • The adsorbent showed excellent selectivity and reusability for U(VI) adsorption. • The adsorbent was employed for recovering U(VI) from wastewater environment. [ABSTRACT FROM AUTHOR]

Here, reaction of a chloromethylated metal-organic framework (MOF) MIL-101 with diaminomaleonitrile (DAMN) following with an amidoximation reaction successfully produced a novel amidoxime functionalized porous material (MIL-101-AO). The chelation of amidoxime group to uranium and the large specific surface area afforded MIL-101-AO excellent selective adsorption ability for U (VI) in aqueous solutions (586 mg·g−1). Furthermore, MIL-101-AO showed much stronger selective adsorption for U (VI) than other co-existing metallic ions in the artificial seawater (removal rate reached 96%). The influence factors on the adsorption process were evaluated by batch adsorption experiments under different condition. The process of adsorbing uranium on MIL-101-AO fitted with the Langmuir model and the pseudo-second-order kinetic model. The △H° and △G° values of uranium adsorption indicated that it was an endothermic heat process; a higher adsorption temperature could promote the adsorption on MIL-101-AO. All the experimental results indicated that MIL-101-AO was an adsorbent with the application value of extracting uranium in seawater. • Amidoxime was first grafted on chloromethylated MIL-101 via diaminomaleonitrile. • Amidoxime-modified MIL-101 shows high U(VI) sorption capacity of 586 mg/g. • High selectivity, U(VI) removal rate reaches 96% in artificial seawater. • Large surface area and strong chelating ability play important role. [ABSTRACT FROM AUTHOR]