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Zirconium-based metal–organic framework nanosheet assembled hydrangea-like architectures were reported and an enhanced iodine capture capacity was achieved. [ABSTRACT FROM AUTHOR]

Carbon-based electrodes play important roles in constructing efficient capacitive deionization (CDI) devices. Therefore, the rational design of carbon materials with optimized structure, composition, and morphology is crucial for further improving the CDI performance. Herein, a novel N, P co-doped eave-like hierarchical porous carbon (NP-EHPC) for CDI is reported. To prepare the NP-EHPC, the core–shell ZIF-8@AF particles are first prepared through the kinetically-controlled growth of zeolitic imidazolate framework-8 (ZIF-8) and polymerization of p-aminophenol and formaldehyde (AF), followed by subsequent pyrolysis and post-doping with phosphorus. Owing to the unique eave-like morphology, presence of abundant mesopores, and co-doping of P and N, the NP-EHPC exhibits a high desalination capacity of 24.14 mg g−1 in 500 mg L−1 NaCl solution at 1.2 V and long cycling stability of over 150 cycles. Moreover, the density functional theory (DFT) calculation results reveal that the co-doping of N and P atoms can greatly enhance the binding energies for Na and Cl atoms and lead to superior electrosorption capacity. This work provides a new insight into the design of high-performance carbon materials for the desalination of brackish water. [ABSTRACT FROM AUTHOR]

We introduce a viable strategy for the fabrication of core–shell ZIF-8@PVP–PDA/Zn by in situ 2-methylimidazole-assisted dopamine self-polymerization. The role of polyvinyl pyrrolidone (PVP) and 2-methylimidazole (2-MI) towards ZIF-8@PVP–PDA/Zn formation is systematically demonstrated. In particular, 2-MI not only is employed as the organic ligand for ZIF-8 but also provides an alkaline environment for the polymerization of dopamine. Moreover, it also protects the ZIF-8 structure from etching. After pyrolysis, the ZIF-8@PVP–PDA/Zn is converted into ant-nest-like hierarchical carbon (ANHC), which has a wide pore distribution, high pore volume (2.35 cm3 g−1) and high nitrogen (7.12%) content. Superior capacitive deionization (CDI) performance (25.4 mg g−1) and stable electrosorption cycles of ANHC are achieved, which demonstrates its potential for CDI applications. [ABSTRACT FROM AUTHOR]

Defect-engineered UiO-66-NH2 was introduced into a polyamide layer to form a thin film nanocomposite (TFN) membrane. Simultaneous enhancements in permeance and selectivity to Na2SO4 solution were achieved. [ABSTRACT FROM AUTHOR]

A polydopamine (PDA)-assisted interface-induction strategy is proposed to transform Zn, Co-zeolitic imidazolate frameworks (ZIFs) into hollow cactus-like carbon sheet/carbon nanotubes (CS/CNTs) for electrocatalysis for the first time. The precursor Zn, Co-ZIFs@PDA was obtained by the coordination between Co2+ (from ZIFs) and N atoms (from PDA). The introduction of PDA achieves simultaneous rational optimization of the composition (N-doping) and structure (2D/1D) by the interface-induction and confinement effect. The advantageous structure and composition endow CS/CNTs with outstanding oxygen reduction reaction activity and durability in alkaline solution. [ABSTRACT FROM AUTHOR]

A phenolic resin (PR)-assisted strategy to transform the zeolitic imidazolate framework (ZIF-67) into hierarchical Co/N-doped carbon rhombic dodecahedra for electrocatalysis is proposed for the first time. The hierarchical ZIF-67@PR composite carbon (HZPC) is obtained by coordinating the kinetic rate of precursors: nucleation/growth of ZIF-67 and polymerization of PR. The introduction of the PR polymer prevents agglomeration of cobalt nanoparticles, creates the well-distributed hierarchical porous structure and optimizes the composition. The advantages of the structure and composition endow HZPC with excellent oxygen reduction reaction (ORR) activity and long-term durability. [ABSTRACT FROM AUTHOR]

Ordered mesoporous carbon (OMC) membranes have broad applications such as size exclusion separation of molecules. In this work, a new method to prepare OMC hollow fiber membranes through a confined soft templating route is developed. In this method, commercialized polymeric hollow fiber ultrafiltration membranes were immersed in an ethanol solution containing a phenolic resin and a Pluronic triblock copolymer. Upon solvent evaporation, the phenolic resin and the surfactant self-assembled into the confined voids of the ultrafiltration membrane. After drying and pyrolysis, OMC hollow fiber membranes were obtained. The OMC hollow fiber membranes possess continuous membrane walls with an average thickness of 113 μm. The membrane wall has a hierarchical pore structure: one coming from hexagonally ordered mesoporous carbon with a pore diameter of ∼4.3 nm and the other being disordered defect holes with a size of 8–50 nm randomly distributed inside the OMC matrix. The gas permeance results indicate that the OMC hollow fiber membranes exhibit Knudsen diffusion behavior confirming their good quality. [ABSTRACT FROM AUTHOR]

Zirconium-based metal-organic framework nanosheet assembled hydrangea-like architectures were reported and an enhanced iodine capture capacity was achieved.

Defect-engineered UiO-66-NH2 was introduced into a polyamide layer to form a thin film nanocomposite (TFN) membrane. Simultaneous enhancements in permeance and selectivity to Na2SO4 solution were achieved.