Supercritical CO2-assisted rapid synthesis of covalent organic framework-based electrocatalyst for efficient two-electron oxygen reduction reaction
Junqi Song, Zhiqiang Zhang, Weiping Li, Chunli Liu, Guodong Feng, Yaqiong Su, Kai Xi, Hong Yi, Hong Yi, Lan Peng
Abstract
Abstract Covalent organic frameworks (COFs) hold significant promise as electrocatalysts, but their synthesis is typically constrained by prolonged reaction times (>72 h), high temperatures ( >120 °C), and the use of organic solvents. Conventional methods also involve multiple freeze-pump-thaw cycles, complicating scalability. Herein, we report a supercritical carbon dioxide (Sc-CO 2 )-assisted strategy for the rapid synthesis of COFs, enabling their direct in-situ growth on carbon substrates. This supercritical-solvothermal approach yields COF@CNT composites that exhibit effective electrocatalytic performance towards the two-electron oxygen reduction reaction (2e − ORR). The resulting catalysts achieve a H 2 O 2 production rate of 94 mol g cat −1 h −1 and a Faradaic efficiency exceeding 95% at 800 mA cm −2 . By reducing the consumption of organic solvents, shortening reaction durations, and circumventing high temperatures, this method provides a scalable and efficient route for COF synthesis. Overall, the Sc-CO 2 strategy provides a promising platform for the rapid development of COF-based electrocatalysts, combining enhanced efficiency, scalability, and environmental compatibility.