Nine-Electron Transfer of Binder Synergistic pi-d Conjugated Coordination Polymers as High-Performance Lithium Storage Materials

To solve the problems such as the dissolution and the poor conductivity of organic small molecule electrode materials, we construct pi-d conjugated coordination polymer Ni-DHBQ with multiple redox-active centers as lithium storage materials. It exhibits an ultra-high capacity of 9-electron transfers, while the pi-d conjugation and the laminar structure inside the crystal ensure fast electron transport and lithium ion diffusion, resulting in excellent rate performance (505.6 mAh g(-1) at 1 A g(-1) after 300 cycles). The interaction of Ni-DHBQ with the binder CMC synergistically inhibits its dissolution and anchors the Ni atoms, thus exhibiting excellent cycling stability (650.7 mAh g(-1) at 0.1 A g(-1) after 100 cycles). This work provides insight into the mechanism of lithium storage in pi-d conjugated coordination polymers and the synergistic effect of CMC, which will contribute to the molecular design and commercial application of organic electrode materials.

Automated summary

In this study, we developed a π-d conjugated coordination polymer Ni-DHBQ with multiple redox-active centers as lithium storage materials, overcoming the problems of dissolution and poor conductivity in organic small molecule electrode materials. Ni-DHBQ exhibited an ultra-high capacity of 9-electron transfers, fast electron transport, and lithium ion diffusion, resulting in excellent rate performance and cycling stability. The interaction with the binder CMC synergistically inhibited dissolution and anchored the Ni atoms. This work provides insights into the mechanism of lithium storage and the synergistic effect of CMC, contributing to the design and application of organic electrode materials.