Release time:2024-12-24  Hits:

• Key Words:ELECTRODES; DESIGN; HYBRID
• Abstract:Bipolar covalent organic frameworks (COFs) with dual active center characteristics have attracted much attention owing to their higher capacity and power/energy output, and good cycling stability, which endow them with high promise for being applied in Faraday-based symmetric supercapacitors (SSCs) and capacitive deionization (CDI). Herein, we fabricated a bipolar covalent organic framework (DQHBA-COF) integrating pyrazine and 1,4-dihydropyrazine species and employed graphene as a conductive substrate to guide the uniform dispersion of the COF on its surface. The DQHBA-COF in the as-prepared nanocomposite (DQHBArGO) displays improved conductivity and excellent ion storage efficiency due to the acquisition of pi-electrons delocalized from graphene. Consequently, the aqueous Na+ SSC based on DQHBArGO-75 achieves a high energy output of 59.2 W h kg-1 and excellent cycling stability. Additionally, the DQHBArGO-75-based symmetric CDI system exhibits an astonishing salt removal capacity of 74.9 mg g-1 along with outstanding recycling ability (no degradation after 100 cycles). This work highlights a new perspective for designing Faraday material-based SCs and CDI systems with symmetrical architectures. DQHBA-COF with bipolar redox-active centers was grown in situ on the conductive graphene surface, endowing symmetric supercapacitors and capacitive deionization systems with a high ion storage capacity and excellent cycling durability.
• Volume:12
• Issue:43
• Translation or Not:no