Effects of Position and Quantity of the Cyano Group in Organic Electrode Materials on Electrochemical Performance

Abstract Recently, organic cathodes have received wide attention as eco‐friendly and sustainable materials for aqueous Zn‐organic batteries. However, the low voltage limits its further development and the related optimization strategies are rarely reported. Herein, three HATN‐based cathode materials containing cyano groups (named O3CN, P3CN, and P6CN) are proposed to reveal the role of cyano groups. The number of cyano groups was positively correlated with the potential, and the position of cyano groups would affect the ion mobility through the steric effect. Furthermore, the cyano group also reduces the solubility of the materials in water, greatly improving the cycle stability under low current density. As a result, the average voltage increased from 0.48 V for HATN to 0.73 V for P6CN, and the capacity retained 88.2 % after 5000 cycles at 5 A g −1 . This study provides a systematic reference for the improvement of the voltage of organic cathode materials in the future.