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Composite polymer electrolytes (CPEs) with smart, stimuli‐responsive characteristics have gained considerable attention owing to their noninvasive manipulation and applications in future technologies. To address this potential, in this work, we demonstrate photoresponsive composite polymer electrolytes, consisting of gel polymer electrolyte (GPE) and spiropyran‐immobilized nanoporous anodic aluminum oxide (SP‐AAO) templates. Under UV irradiation, the close SP form isomerizes to the open merocyanine (MC) form, creating extremely polarized AAO surfaces; whereas, under visible light irradiation, the MC form reverts to the SP form, creating neutral surface conditions. The electrostatic interactions between ions and AAO surfaces are investigated by attenuated total reflection Fourier‐transform infrared (ATR‐FTIR) spectroscopy. Moreover, the behavior of ionic conductivity of the GPE@SP‐AAO is found to be consistent with the kinetics of isomerization tracked by UV‐Vis spectroscopy. This work provides a promising platform for developing next‐generation photoelectronic smart devices. [ABSTRACT FROM AUTHOR]

Over the past few decades, stimuli‐responsive materials have been widely applied to porous surfaces. Permeability and conductivity control of ions confined in nanochannels modified with stimuli‐responsive materials, however, have been less investigated. In this work, the permeability and conductivity control of ions confined in nanochannels of anodic aluminum oxide (AAO) templates modified with thermo‐responsive poly(N‐isopropylacrylamide) (PNIPAM) brushes are demonstrated. By surface‐initiated atom transfer radical polymerization (SI‐ATRP), PNIPAM brushes are successfully grafted onto the hexagonally packed cylindrical nanopores of AAO templates. The surface hydrophilicities of the membranes can be reversibly altered because of the lower critical solution temperature (LCST) behavior of the PNIPAM polymer brushes. From electrochemical impedance spectroscopy (EIS) analysis, the temperature‐gating behaviors of the AAO‐g‐PNIPAM membranes exhibit larger impedance changes than those of the pure AAO membranes at higher temperatures because of the aggregation of the grafted PNIPAM chains. The reversible surface properties caused by the extended and collapsed states of the polymer chains are also demonstrated by dye release tests. The smart thermo‐gated and ion‐controlled nanoporous membranes are suitable for future smart membrane applications. [ABSTRACT FROM AUTHOR]

The separation of alkanes, particularly monobranched and dibranched isomers, is of paramount importance in the petrochemical industry for optimizing the feedstock of ethylene production as well as for upgrading the octane number of gasoline. Here, we report the full separation of linear/monobranched alkanes from their dibranched isomers by a robust and easily scalable metal‐organic framework material, Co3(HCOO)6. The compound completely excludes dibranched alkanes but adsorbs their linear and monobranched isomers, as evidenced by single‐component and multicomponent adsorption measurements. More importantly, the material exhibits excellent performance in separating naphtha and is capable of providing high quality feedstock for the production of ethylene and gasoline components with high octane number, making it a promising candidate for naphtha separation in petrochemical industry. [ABSTRACT FROM AUTHOR]

Alkane isomers, hydrocarbon separation, metal-organic frameworks, naphtha, octane number Keywords: alkane isomers; hydrocarbon separation; metal-organic frameworks; naphtha; octane number EN alkane isomers hydrocarbon separation metal-organic frameworks naphtha octane number 11748 11748 1 08/19/21 20210816 NES 210816 B Naphtha was separated b by using a easily attainable metal-organic framework, Co SB 3 sb (HCOO) SB 6 sb , through selective molecular exclusion of alkane isomers with different degrees of branching. Cover Feature: Upgrading Octane Number of Naphtha by a Robust and Easily Attainable Metal-Organic Framework through Selective Molecular Sieving of Alkane Isomers (Chem. Eur. J. 46/2021). [Extracted from the article]