Tailoring black phosphorus nanostructures for high-energy and fast-charging potassium ion batteries: A chemicophysical/electrochemical design strategy

The quest for high energy density and rapid charging in potassium ion batteries (PIBs) employing black phosphorus (BP) has been hindered by its inherent challenges, including low voltage output and sluggish ion transport kinetics. To overcome these limitations, a meticulously engineered ultrathin BP nanostructure, equipped with a precise adsorption valve controller and an oriented crystallization, is encapsulated within N, B co-doped carbon nanospheres that contain Co single atoms/nanoclusters (Co-NBC). This encapsulation is further fortified by (E)-2-chloro-4-((3’-chloro-4’-hydroxyphenyl)diazinyl)phenyl acrylate (CA), resulting in a structure that offers an extended voltage window and enhanced cascaded ion transport, interface, and anode. The Co-NBC@BP@CA structure demonstrates remarkable performance, boasting high energy density, high electrochemical stable window (ESW) of 3.36 V, and impressive low-temperature adaptability ranging from −55–0 °C. These are attributed to the robust F/O interactions and the reconstructed hydrogen bonds. This innovative chemicophysical/electrochemical design strategy not only enhances the performance of BP-based PIBs but also sheds light on the pivotal roles of spin-orbit coupling and cascaded ion transport in the development of high-energy PIBs. This advancement opens up new avenues for further research and development in the field, potentially leading to the creation of more efficient and sustainable energy storage solutions.