In this study, we prepared a series of conjugated microporous polymers (CMPs) through Sonogashira–Hagihara cross-couplings of a tetrabenzonaphthalene (TBN) monomer with pyrene (Py), tetraphenylethylene (TPE), and carbazole (Car) units and examined their chemical structures, thermal stabilities, morphologies, crystallinities, and porosities. TBN–TPE-CMP possessed a high surface area (1150 m2 g–1) and thermal stability (T d10 = 505 °C; char yield = 68 wt %) superior to those of TBN–Py-CMP and TBN–Car-CMP. To improve the conductivity of the TBN-CMP materials, we blended them with highly conductive single-walled carbon nanotubes (SWCNTs). Electrochemical measurements revealed that the TBN–Py-CMP/SWCNT nanocomposite had high capacitance (430 F g–1) at a current density of 0.5 A g–1 and outstanding capacitance retention (99.18%) over 2000 cycles; these characteristics were superior to those of the TBN–TPE-CMP/SWCNT and TBN–Car-CMP/SWCNT nanocomposites.

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There is currently a pursuit of synthetic approaches for designing porous carbon materials with selective CO2 capture and/or excellent energy storage performance that significantly impacts the environment and the sustainable development of circular economy. In this study we prepared a new bio-based benzoxazine (AP-BZ) in high yield through Mannich condensation of apigenin, a naturally occurring phenol, with 4-bromoaniline and paraformaldehyde. We then prepared a PA-BZ porous organic polymer (POP) through Sonogashira coupling of AP-BZ with 1,3,6,8-tetraethynylpyrene (P-T) in the presence of Pd(PPh3)4. In situ Fourier transform infrared spectroscopy and differential scanning calorimetry revealed details of the thermal polymerization of the oxazine rings in the AP-BZ monomer and in the PA-BZ POP. Next, we prepared a microporous carbon/metal composite (PCMC) in three steps: Sonogashira coupling of AP-BZ with P-T in the presence of a zeolitic imidazolate framework (ZIF-67) as a directing hard template, affording a PA-BZ POP/ZIF-67 composite; etching in acetic acid; and pyrolysis of the resulting PA-BZ POP/metal composite at 500 °C. Powder X-ray diffraction, thermogravimetric analysis, scanning electron microscopy, transmission electron microscopy, and Brunauer–Emmett–Teller (BET) measurements revealed the properties of the as-prepared PCMC. The PCMC material exhibited outstanding thermal stability (Td10 = 660 °C and char yield = 75 wt%), a high BET surface area (1110 m2 g–1), high CO2 adsorption (5.40 mmol g–1 at 273 K), excellent capacitance (735 F g–1), and a capacitance retention of up to 95% after 2000 galvanostatic charge–discharge (GCD) cycles; these characteristics were excellent when compared with those of the corresponding microporous carbon (MPC) prepared through pyrolysis of the PA-BZ POP precursors with a ZIF-67 template at 500 °C.

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In this study, we used classical and simple Sonogashira couplings to construct three 1,3,4-oxadiazole-linked conjugated microporous polymers (OXD-CMPs) through the reaction of 2,5-bis­(4-bromophenyl)-1,3,4-oxadiazole (OXD-Br2) as a common partner with the structurally diverse units of ethynyl triphenylamine, tetraphenylethene, and pyrene, respectively. We used several methods, both spectroscopic and microscopic, to characterize the three OXD-CMPs. Each OXD-CMP displayed a high thermal stability. The Py-OXD-CMP possessed pores having sizes in the range 1.20–2.25 nm and a high surface area (298 m2 g–1). These OXD-CMPs interacted with singled-walled carbon nanotubes (CNTs), stabilized through noncovalent π–π interactions, to afford OXD-CMP/CNT composites that were suitable for supercapacitor devices. Among our OXD-CMP/CNT composites, the Py-OXD-CMP/CNT composite offered a specific capacitance of 504 F g–1 and a superior capacitance retention (91.1%) over 2000 cycles.

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In this study, we successfully synthesized, designed, and constructed three porous organic polymers (POPs) without or with acetylene as the bridgeBz-Th, TPA-Th, and P-Th-POPsthrough a robust and efficient coupling reaction of 2,8dibromothianthrene (Th-Br 2 ) as a building unit with 1,3,5-tris(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzene (Bz-3BO), tris(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)amine (TPA-3BO), and 1,3,6,8-tetraethynylpyrene (P-T). Our POP materials displayed exceptional heat stability (char yields of more than 70% for each POP) and superior Brunauer−Emmett−Teller surface areas. According to electrochemical testing, a P-Th-POP-containing acetylene group as a bridge has a specific capacitance of 217 F g −1 at 0.5 A g −1 and an excellent cycling stability of over 5000 times at 10 A g −1 . Compared to other porous materials, P-Th-CMP exhibits the highest specific capacitance, which may be attributed to its enormous surface area and extended conjugation system.

Extended π-conjugated microporous polymers (CMPs) are useful as organic anode or cathode materials in lithium-ion batteries (LIBs), overcoming the issue of small organic molecules becoming soluble in the electrolytes during charge–discharge cycles. In this study, we constructed two CMPs (Py-A-CMP, TPE-A-CMP) containing anthraquinone (A) moieties (as redox-active units and sources of CO groups) and applied them as organic cathodes in LIBs. We synthesized the Py-A-CMP and TPE-A-CMP through Sonogashira–Hagihara couplings of 2,6-dibromoanthraquinone (A-Br2) with tetraethynylpyrene (Py-T) and tetraethynyltetraphenylethene (TPE-T), respectively. The TPE-A-CMP displayed high thermal decomposition temperatures (up to 539 °C) and char yields (up to 53 wt %). Electrochemical tests revealed that Py-A-CMP and TPE-A-CMP delivered discharge capacities (196.6 and 164.7 mAh g–1 at a C-rate of 0.1C, respectively) higher than those of other CMP materials. The capacity retention of TPE-A-CMP was 163 mAh g–1 (99.3%) over 400 cycles. The corresponding cells incorporating Py-T-CMP and TPE-T-CMP also exhibited excellent rate capability performance, maintaining discharge capacities of approximately 79 and 49 mAh g–1, respectively, at a high charge/discharge rate of 5C. Scanning electron microscopy confirmed the superior stability of both CMPs, revealing that these electrode materials remained intact, without any surface crack formation, during long-term cycling.