Thianthrene- and Thianthrene Tetraoxide-Functionalized\nConjugated Microporous Polymers for Efficient Energy Storage

Supercapacitors (SCs),\nwith their exceptional properties, present\na promising solution to the ongoing energy crisis by meeting the increasing\ndemand for high-energy storage devices. Conjugated microporous polymers\n(CMPs) offer a range of sizes, precisely controlled porosities, impressive\nintrinsic porosity, remarkable stability, and customizable structures\nand functionalities. These attributes collectively make CMPs cost-effective\nmaterials for energy storage applications. In this research, we effectively\ncreated three organic electrodes based on CMPs for energy storage\nvia the Suzuki coupling reaction of 1,3,6,8-tetrakis(4-bromophenyl)pyrene\n(PyPh-Br<sub>4</sub>) and benzene-1,4-diboronic acid (BZ-2B(OH)<sub>2</sub>) with 2,8-dibromothianthrene (Th-Br<sub>2</sub>) or 3,7-dibromodibenzothiophene <i>S</i>, <i>S</i>-dioxide (SU-Br<sub>2</sub>) or 2,8-dibromothianthrene-5,5′,10,10′-tetraoxide\n(DSU-Br<sub>2</sub>) to produce PyPh-BZ-Th, PyPh-BZ-SU, and PyPh-BZ-DSU\nCMP, respectively. Their thermal stability was examined using TGA\nmeasurements, and both PyPh-BZ-Th CMP and PyPh-BZ-SU CMP displayed\nT<sub><i>d</i>10</sub> of 540 and 467 °C with high\ncarbon reside up to 70 wt % at 800 °C. Electrochemical performance\nfor these materials was evaluated using cyclic voltammetry (CV) and\ngalvanostatic charge–discharge (GCD). Within a three-electrode\nsetup, specific capacitances of 617, 538, and 596 F g<sup>–1</sup> for PyPh-BZ-Th, PyPh-BZ-SU, and PyPh-BZ-DSU CMPs were recorded by\nGCD at 0.5 A g<sup>–1</sup>. To obtain a more practical and\naccurate evaluation, we further constructed symmetric devices for\neach CMP. Using GCD curves, the specific capacitances were found to\nbe 187, 63, and 105 F g<sup>–1</sup>, respectively, for PyPh-BZ-Th,\nPyPh-BZ-SU, and PyPh-BZ-DSU CMPs. The high capacitances of the synthesized\nCMPs in this study, comparable to those of other reported porous CMPs,\ncan be attributed to electronegative moieties, such as sulfur (S)\nand sulfone (SO<sub>2</sub>) groups. These groups enhance electrostatic\ninteractions and improve the wettability of the electrodes. This study\ndemonstrates that using the Suzuki coupling reaction technique, CMPs\nincorporating Py, Th, and DSU moieties can be effectively produced\nfor energy storage applications.