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Crystals of a metal–organic framework, UiO-66, are grown on electrospun crosslinked poly-cyclodextrin (poly-CD) fibrous membranes with an ultrahigh coverage, and polyaniline (PANI) is further confined within the MOF pores. The obtained PANI@UiO-66/poly-CD membranes are used as free-standing electrodes towards use in wearable energy-storage devices. [ABSTRACT FROM AUTHOR]

Portable and flexible energy devices demand lightweight and highly efficient catalytic materials for use in energy devices. An efficient water splitting electrocatalyst is considered an ideal future energy source. Well‐aligned high‐surface‐area electrospun polymers of intrinsic microporosity (PIM‐1)‐based nitrogen‐doped carbon nanofibers were prepared as a free‐standing flexible electrode. A non‐noble‐metal catalyst NiOOH/Ni(OH)2 was precisely deposited over flexible free‐standing carbon nanofibers by using atomic layer deposition (ALD). The morphology, high surface area, nitrogen doping, and Ni states synergistically showed a low onset potential (ηHER=−40 and ηOER=290 mV vs. reversible hydrogen electrode), small overpotential at η10 [oxygen evolution reaction (OER)=390.5 mV and hydrogen evolution reaction (HER)=−147 mV], excellent kinetics (Tafel slopes for OER=50 mV dec−1 and HER=41 mV dec−1), and high stability (>16 h) towards water splitting in an alkaline medium (0.1 m KOH). The performance was comparable with that of state‐of‐the‐art noble‐metal catalysts (e.g., Ir/C, Ru/C for OER, and Pt/C for HER). Post‐catalytic characterization with X‐ray photoelectron spectroscopy (XPS) and Raman spectroscopy further proved the durability of the electrode. This study provides insight into the design of 1D‐aligned N‐doped PIM‐1 electrospun carbon nanofibers as a flexible and free‐standing NiOOH/Ni(OH)2 decorated electrode as a highly stable nanocatalyst for water splitting in an alkaline medium. A simple and controlled synthesis of flexible, free‐standing, binder‐free, atomically deposited NiOOH/Ni(OH)2 on well‐aligned N‐doped PIM‐CF and its application towards overall water splitting (i.e., hydrogen evolution reaction and oxygen evolution reaction) in an alkaline medium. [ABSTRACT FROM AUTHOR]

In this study, thermally crosslinked hydrolyzed polymers of intrinsic microporosity (HPIM)/polybenzoxazine electrospun nanofibrous membranes (NFMs) are successfully produced. The nanofibers having 800 ± 260 to 670 ± 150 nm average fiber diameters from HPIM and blends of HPIM/ benzoxazine (BA‐a) ranging from HPIM:(BA‐a) weight ratio of 9:1 to 2:1 w/w are produced by electrospinning. Self‐standing HPIM/(BA‐a) NFMs are thermally step‐wise cured resulting in crosslinked HPIM/Poly(BA‐a) NFMs. Structural characterization of as‐electrospun HPIM/(BA‐a) and crosslinked HPIM/Poly(BA‐a) NFM is conducted by FT‐IR spectroscopy to trace the ring opening and crosslinking reactions. Elemental analysis and XPS studies show an increase in carbon content and reduction in nitrogen content due to the crosslinking reaction. Decomposition temperature (Td) of HPIM NFM increases from 218 to 270 °C with the crosslinking based on the DSC. DMA analysis shows that the mechanical strength of the NFMs has increased significantly with crosslinking. Young's moduli of HPIM NFM is increased from 16 ± 7 to 67 ± 1 MPa for crosslinked HPIM/Poly(BA‐a)%33 NFM. Similarly, higher storage modulus is observed for HPIM/Poly(BA‐a) NFMs compared to HPIM NFM. The crosslinked HPIM/Poly(BA‐a) NFMs keep their fibrous morphology after solvent treatment in dimethylformamide revealing their structural stability compared to pristine HPIM NFM. Electrospun hydrolyzed polymers of intrinsic microporosity (HPIM) nanofibrous membranes (NFMs) are successfully crosslinked with benzoxazine monomer (BA‐a) to improve mechanical, thermal, and structural properties of the HPIM NFM. [ABSTRACT FROM AUTHOR]

Nitrile groups in the polymer of intrinsic microporosity PIM-1 were reduced to primary amines using borane complexes. In adsorption experiments, the novel amine-PIM-1 showed higher CO 2 uptake and higher CO 2 /N 2 sorption selectivity than the parent polymer, with very evident dual-mode sorption behavior. In gas permeation with six light gases, the individual contributions of solubility and diffusion to the overall permeability was determined via time-lag analysis. The high CO 2 affinity drastically restricts diffusion at low pressures and lowers CO 2 permeability compared to the parent PIM-1. Furthermore, the size-sieving properties of the polymer are increased, which can be attributed to a higher stiffness of the system arising from hydrogen bonding of the amine groups. Thus, for the H 2 /CO 2 gas pair, whereas PIM-1 favors CO 2 , amine-PIM-1 shows permselectivity toward H 2 , breaking the Robeson 2008 upper bound.