Modulating Bonding States and Stability of Conductive Coordination Polymers
Huichao Dai, Yueyue Cao, Lei Chen, Guoqun Zhang, Linnan Guan, Minglei Mao, Chengliang WangABSTRACT
Conductive coordination polymers (CCPs) could combine the merits of both conductive polymers and metal‐organic frameworks (MOFs) and hence have attracted extensive attention for various applications. However, the modulation of their properties is challenging and rarely studied. Herein, three CCPs, denoted as Cu─6O, Cu─6N, and Cu─3O3N, featuring Cu─O 4 , Cu─(NH) 4 , and Cu─O 2 (NH) 2 units respectively, are constructed to systematically investigate the effect of the ligating atoms and bonding states on the properties. Spectroscopic and theoretical analyses reveal that Cu─O bonds are dominated by electrostatic interactions, whereas Cu─N bonds exhibit stronger covalent character, and the mixed Cu─O 2 (NH) 2 unit further enhances the overall bond strength by optimizing orbital hybridization and energy matching. Consequently, Cu─6O shows the weakest Cu─X (X═O or NH) bonds, poorest thermal stability and undergoes irreversible degradation upon base conditions at pH above ∼9.5, while also suffering severe structural degradation under electrochemical condition. The degradation mechanism was also revealed. Conversely, the stronger coordination bonds in Cu─6N and Cu─3O3N endow them with superior thermal, chemical, and electrochemical stability. This work highlights the essential role of ligating atoms in determining the bonding states and provides a design principle for developing robust CCPs.