Fiber-shaped supercapacitors (FSCs) are promising energy storage devices that meet the growing demands for the miniaturization, flexibility, and compatibility of wearable electronics. However, when compared with batteries, the low energy density remains the main limitation to practical applications. A conjugated microporous polymer (CMP) network synthesized using Buchwald−Hartwig cross-coupling reactions featured tailorable porous structures, reversible redox chemistry, and demonstrated highly efficient capacitive performance. Herein, the CMP network that grafted on carbon nanotube fibers (CNF@CMP) with high areal specific capacitance (671.9 mF cm −2 at a current density of 1 mA cm −2 ) was successfully achieved for a polytriphenylamine (PTPA)based network. All-solid-state symmetrical-twisted CNF@PTPA FSCs fabricated with PVA/H 3 PO 4 as a gel electrolyte exhibited a high specific areal capacitance of 398 mF cm −2 (0.28 mA cm −2 ), a maximal operating voltage of 1.4 V, and an energy density of 18.33 μWh cm −2 . Moreover, they showed excellent flexibility and mechanical stability retaining 84.5% of the initial capacitance after 10,000 bending cycles. These materials provide a new route to high-performance wearable supercapacitors (HPWS) with wide potential applications in wearable electronics, as shown by the examples provided.

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Conjugated microporous polymers (CMPs) are promising electrode materials for electrochemical energy storage, but their poor redox activity and electric conductivity limit their practical applications. Herein, CMPs obtained from the Buchwald–Hartwig coupling reaction using a spirobifluorene bromide core and p-phenylenediamine linker (SACMPs) are grafted onto the multiwalled carbon nanotube (MWCNT) via one-step in situ polymerization. The as-prepared composite (MWCNT@SACMP) exhibits a high surface area of 514 m2 g–1, excellent redox activity, and reasonable conductivity. As expected, MWCNT@SACMP presents a high specific capacitance of 594 F g–1 at a current density of 1.0 A g–1 when the content of MWCNTs is around 10 wt %, which is improved by 252% from the 236 F g–1 of SACMP. A symmetric two-electrode supercapacitor assembled with MWCNT@SACMP shows an efficient specific capacitance of 254 F g–1 and an energy density of 28.53 W h kg–1 at a power density of 900 W kg–1 and can retain 84.38% of its initial capacitance after 6000 cycles. This work thus presents a promising CMP/MWCNT composite material for supercapacitor energy storage.

Efficient materials for electrochemical energy storage have received much attention. Herein we report a green metal‐free route to synthesize pyridyl conjugated microporous polymers (PCMPs) as precursors for nitrogen‐doped porous carbon microspheres (NCMs) with high surface areas up to 1232 m2 g−1 via a simple carbonization method. The resulting NCMs as supercapacitor electrodes exhibit high specific capacitance of 324 F g−1 at a current density of 0.1 A g−1, and high rate ability (182 F g−1 at 10 A g−1), and excellent cyclability (remained >97 % of initial capacitance at 2 A g−1 after 10000 cycles). This work also presents that molecular engineering of PCMP precursor, pyrolysis temperature and charge/discharge cycling allow the electrochemical energy storage properties of the NCMs to be controlled.

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Well-defined amphiphilic diblock copolymer poly (methyl methacrylate)-b-poly (N-isopropylacrylamide) grafted hollow spheres (HS-g-PMMA-b-PNIPAM) hybrid materials were synthesized via metal-free surface-initiated atom transfer radical polymerization (SI-ATRP). The ATRP initiators α-Bromoisobutyryl bromide (BIBB) were attached onto hollow sphere surfaces through esterification of acyl bromide groups and hydroxyl groups. The synthetic ATRP initiators (HS-Br) were further used for the metal-free SI-ATRP of methyl methacrylate (MMA) and N-isopropyl acrylamide (NIPAM) using 10-phenylphenothiazine (PTH) as the photocatalyst. The molecular weight of the polymers, structure, morphology, and thermal stability of the hybrid materials were characterized via gel permeation chromatography (GPC), X-ray photoelectron spectroscopy (XPS), 1H-nuclear magnetic resonance spectroscopy (1H NMR), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), and thermogravimetric analysis (TGA), respectively. The results indicated that the ATRP initiator had been immobilized onto HS surfaces successfully followed by metal-free SI-ATRP of MMA and NIPAM, the Br atom had located at the end of the main PMMA polymer chain, and the polymerization process possessed the characteristic of controlled/“living” polymerization. The thermal stability of the hybrid materials was increased significantly compared to the pure PMMA and PNIPAM.

Well-defined polymer brushes attached to nanoparticles offer an elegant opportunity for surface modification because of their excellent mechanical stability, functional versatility, high graft density as well as controllability of surface properties. This study aimed to prepare hybrid materials with good dispersion in different solvents, and to endow this material with certain fluorescence characteristics. Well-defined diblock copolymers poly (styrene)-b-poly (hydroxyethyl methyl acrylate)–co-poly (hydroxyethyl methyl acrylate- rhodamine B) grafted silica nanoparticles (SNPs-g-PS-b-PHEMA-co-PHEMA-RhB) hybrid materials were synthesized via surface-initiated activators regenerated by electron transfer atom transfer radical polymerization (SI-ARGET ATRP). The SNPs surfaces were modified by 3-aminopropyltriethoxysilane (KH-550) firstly, then the initiators 2-Bromoisobutyryl bromide (BIBB) was attached to SNPs surfaces through the esterification of acyl bromide groups and amidogen groups. The synthetic initiators (SNPs-Br) were further used for the SI-ARGET ATRP of styrene (St), hydroxyethyl methyl acrylate (HEMA) and hydroxyethyl methyl acrylate-rhodamine B (HEMA-RhB). The results indicated that the SI-ARGET ATRP initiator had been immobilized onto SNPs surfaces, the Br atom have located at the end of the main polymer chains, and the polymerization process possessed the characteristic of controlled/“living” polymerization. The SNPs-g-PS-b-PHEMA-co-PHEMA-RhB hybrid materials show good fluorescence performance and good dispersion in water and EtOH but aggregated in THF. This study demonstrates that the SI-ARGET ATRP provided a unique way to tune the polymer brushes structure on silica nanoparticles surface and further broaden the application of SI-ARGET ATRP.

Amphiphilic copolymers, poly(styrene)-block-Tb complex (PS-b-Tb complex), were synthesized by reversible addition fragmentation chain transfer (RAFT) polymerization. The honeycomb structured porous films were fabricated via dropping the PS-b-Tb complex copolymer solutions on glass substrates by the breath figures method (BFM). The structure and composition of the amphiphilic copolymer PS-bTb complex were confirmed by gel permeation chromatography (GPC), Fourier transform infrared spectroscopy (FT-IR) and 1 H nuclear magnetic resonance spectroscopy ( 1 H NMR). The surface morphology and elemental mapping of the highly ordered porous films were investigated by field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDX) and laser scanning confocal microscopy (LSCM). The results indicated that the solvent type and copolymer concentration can affect the surface morphology of the porous films. The average diameter of the pores in the porous films decreased with the polymer concentration and the molecular weight of the copolymers increased. The FESEM-EDX analysis further verified that the hydrophilic groups (Tb complex groups) were mainly distributed at the pore wall, instead of at the outer surface layer of the films, which was consistent with the LSCM results.