• Xu, J.; Tang, W.; Yang, C.; Manke, I.; Chen, N.; Lai, F.; Xu, T.; An, S.; Liu, H.; Zhang, Z.; Cao, Y.; Wang, N.; Zhao, S.; Niu, D.; Chen, R.: A Highly Conductive COF@CNT Electrocatalyst Boosting Polysulfide Conversion for Li-S Chemistry. ACS Energy Letters 6 (2021), p. 3053-3062

10.1021/acsenergylett.1c00943

Abstract:
The catalysis of covalent organic frameworks (COFs) in Li–S chemistry is largely blocked by a weak chemical interaction and low conductivity. Herein, a new kind of diketopyrrolopyrrole (DPP)-based COF is in situ fabricated onto the carbon nanotube (CNT) surface (denoted as COF@CNT) to uncover the electrocatalysis behavior by its strong chemical interaction and highly conductive property. We declare that the electrocatalytic activity of DPP-COF can be maximized by introducing an appropriate content of CNT (66 wt %); the analyses including density functional theory calculations, X-ray photoelectron spectroscopy, Fourier transform infrared, and Raman show that the DPP moiety can mediate the conversion of polysulfides contributed by a C═O/C–O bonding conversion. Hence, the modified battery shows a 0.042% decay rate over 1000 cycles and achieves a desirable capacity of 8.7 mAh cm–2 with 10 mg cm–2 sulfur loading and lean electrolyte (E/S = 5). This work will inspire the rational design of COF@support hybrids for various electrocatalysis applications.