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With the rapid development of energy storage technology, the operation of portable and wearable devices is inseparable from high energy density power supplies. However, the demand for high performance supercapacitors in movable smart electronics is still restrained by their insufficient areal capacitance and limited power/energy densities. In addition, some electroactive materials, including metal oxides, conductive polymers, graphene, porous carbons, etc., are inevitable to use extra adhesives for the preparation of electrode materials. In this work, integrated hierarchical graphitic porous carbon membranes used as the electrodes without adhesives are successfully synthesized, via pyrolyzing poly(ionic liquid)s (PILs)‐metal organic frameworks (MOFs) composite membranes. The asymmetric supercapacitor is assembled by the carbonized PIL‐MOF composite membrane and PILs‐derived porous carbon membrane, and exhibits significant areal capacitance with remarkable power and energy densities. In the two‐electrode system, the areal capacitance can reach 9.5 F cm−2 with an energy density of 1.91 mWh cm−2. In the fabricated all‐solid‐state supercapacitors, the areal capacitance and energy density achieved 3.2 F cm−2 and 0.65 mWh cm−2, respectively, exceeding most reported ones. Therefore, the integrated carbon membrane electrodes with high areal capacitance reveal great potential in miniaturized devices, and further show a wider application scope through regulating PILs. [ABSTRACT FROM AUTHOR]

Topological geometry of poly(ionic liquid)s (PILs), such as brush‐like, knot‐like, hyperbranched and randomly coiled, often exerts a strong influence on their self‐assembly behaviors. As a primary topological form, the cyclic topology‐derived effects have not been investigated on PILs, which concerns synergy of charges and zero chain end. Herein, linear and cyclic poly(ionic liquid) copolymers (co‐PILs) with randomly distributed counter anions of B(Ph)4− and Br− by a template method in combination with a follow‐up partial anion exchange is prepared. The self‐assembly phenomena of linear and cyclic co‐PILs are studied in selective solvents, where the hydrophobic counter anions B(Ph)4− and hydrophilic counter anions Br− aggregated to form cores and corona in the assembled nanospheres, showing the average size of cyclic co‐PILs nanospheres is 46.2% smaller (≈120 nm) than linear co‐PILs nano‐assemblies (≈176 nm). Based on the CGMD simulations, the authors speculate that the spherical aggregates are formed by transitioning from micelles with gradient block‐like structures, which formed by enriched hydrophobic counter anions in the core and enriched hydrophilic counter anions in the corona. These results indicate a novel synergy of topology effects and dynamic anion movements, as revealed by cyclic co‐PIL self‐assembly in this work. [ABSTRACT FROM AUTHOR]

Abstract Charged cyclic polymers, e.g. cyclic DNAs and polypeptides, play enabling roles in organisms, but their synthesis was challenging due to the well-known "polyelectrolyte effect". To tackle the challenge, we developed a templated method to synthesize a library of imidazolium and pyridinium based cyclic poly(ionic liquid)s. Cyclic templates, cyclic polyimidazole and poly(2-pyridine), were synthesized first through ring-closure method by light-induced Diels−Alder click reaction. Through quaternization of cyclic templates followed by anion metathesis, the cyclic poly(ionic liquid)s were synthesized, which paired with varied counter anions. [ABSTRACT FROM AUTHOR]