Controlled Microwave-Assisted Synthesis of Covalent Organic Frameworks Opens the Way Toward More Suitable Porous Supercapacitor Electrodes

Seeking efficient materials is still the key process for achieving high-performance electrical double-layer capacitor-type supercapacitors. In the present work, the synthesis of a well-known covalent organic framework, COF-5, was revisited and optimized by a microwave irradiation-assisted solvothermal approach. The highest Brunauer–Emmett–Teller specific surface area ever of 2600 m 2 g –1 was achieved for this material along with a reaction yield of >90% with a reduced reaction time. This study provides further evidence on the real convenience of using microwave irradiation as an alternative route for efficiently synthesizing covalent organic framework-based materials. Indeed, the electrical conductivity increases by 4 orders of magnitude up to 2.35 × 10 –2 S cm –1 . Furthermore, the synthesized COF-5 was evaluated as-prepared or together with conducting additives as active electrode materials for supercapacitor applications. Accordingly, a specific capacitance of 100 F g –1 at 2 mV s –1 was obtained after the activation process. Importantly, the better organization of the structure of the COF strongly enhances its stability over a potential range of 1.3 V at 100 mV s –1 for 100 000 cycles in aqueous electrolytes.