Bipolar Conjugated Microporous Polymer Anchored Graphene Hybrids Towards High-Performance Zinc−Organic Batteries

Redox organic polymers have emerged as cathode candidates for zinc−organic batteries (ZOBs) due to their high electrochemical activity, environmental friendliness and structural designability. However, most organic polymers are confined to limited active sites and unstable structures, resulting in low capacity and poor cycle performance. Here, we propose an effective inorganic/organic anchoring strategy in which bipolar conjugated microporous polymers (CMPs) are anchored on the reduced graphene oxide (rGO) surface to form rGO@CMPs hybrids via π-π stacking and hydrogen bonding interactions. Based on rGO@CMPs cathode, the assembled ZOBs can provide the capacity up to 378 mAh g−1 at 0.2 A g−1, an impressively high energy density of 251 Wh kg−1 and a capacity retention of 90.1% after 25, 000 cycles. The outstanding electrochemical performances of rGO@CMPs root in the unique anchored structure guided by its novel molecular design. On the one hand, the well-designed molecule structure endows bipolar CMPs with high-density dual redox-active centers, which allow for alternate storage of Zn2+/CF3SO3− ions to improve the capacity. On the other hand, the introduced rGO can firmly interact with CMPs to suppress its dissolution, resulting in fast reaction kinetics, excellent structural stability and high ion accessibility. This molecular design-guided inorganic/organic anchoring strategy enriches the approach for cathode construction and improves the high performance of ZOBs.