Layered S‐Bridged Covalent Triazine Frameworks via a Bifunctional Template‐Catalytic Strategy Enabling High‐Performance Zinc‐Ion Hybrid Supercapacitors

Abstract

AbstractExploring covalent triazine frameworks (CTFs) with high capacitative activity is highly desirable and challenging. Herein, the S‐rich CTFs cathode is pioneeringly introduced in Zn‐ion hybrid supercapacitors (ZSC), achieving outstanding capacity and energy density, and satisfactory anti‐freezing flexibility. Specifically, the S‐bridged CTFs are synthesized by a bifunctional template‐catalytic strategy, where ZnCl2 serves as both the catalyst/solvent and in situ template to construct triazine frameworks with interconnected pores and layered gaps. The resultant CTFs (CTFS‐750) are employed as a reasonable pattern‐like system to more deeply scrutinize the synergistic effect of S‐bridged triazine and layered porous architecture for polymer‐based cathodes in Zn‐ion storage. The experimental results indicate that the adsorption barriers of Zn‐ions on CTFS‐750 are effectively weakened, and accessible Zn2+‐absorption sites provided by the C─S─C and C═N bonds have been confirmed via DFT calculations. Consequently, the CTFS‐750 cathode‐assembled ZSC displays an ultra‐high capacity of 211.6 mAh g−1 at 1.0 A g−1, an outstanding energy density of 202.7 Wh kg−1, and attractive cycling performance. Moreover, the resulting flexible ZSC device shows superior capacity, good adaptability, and satisfactory anti‐freezing behavior. This approach sheds new light on constructing advanced polymer‐based cathodes at the atom level and paves the way for fabricating high‐performance ZSC and beyond.