Bioinspired Neuron-Like Conjugated Polymer Chains@MXene of Polymer-Based Anode for High-Rate Potassium-Ion Batteries.

Polymer electrode materials (PEMs), characterized by tunable and flexible molecular structures, hold great promise for potassium storage. However, their practical implementation is hindered by inherently low electrical conductivity. Herein, we synthesize a novel bioinspired neuron-like networks by controllably grafting conjugated polymer nanofilaments onto MXene nanosheets (denoted as CMP@BrMXene). This distinctive neuron-like architecture, along with the resulting cytoplast-like MXene junctions, not only creates abundant continuous pathways in multiple directions to facilitate rapid and uniform electron transport, but also exposes additional active sites for K+ coordination within the polymer-based anode. Leveraging these unique structures, the CMP@BrMXene electrodes deliver a high reversible specific capacity of 525 mAh g-1 at 30 mA g-1 and exhibit outstanding rate capability, retaining 119.8 mAh g-1 at 3000 mA g-1. Impressively, a durable capacity retention of 88.4% is maintained after 3000 cycles at 1 A g-1. Furthermore, operando XPS and theoretical analysis provide new insights into the redox reaction mechanism, confirming that MXene can streamline the multi-electron redox process and enhance the utilization of redox-active sites. These findings underscore that the all-integrated CMP@BrMXene electrodes, with MXene serving as multifunctional junctions, establish a new paradigm for developing high-performance potassium storage anodes.