Carbonized Polymer Dots for Controlling Construction of MoS2 Flower‐Like Nanospheres to Achieve High‐Performance Li/Na Storage Devices

Abstract Despite being one of the most promising materials in anode materials, molybdenum sulfide (MoS 2 ) encounters certain obstacles, such as inadequate cycle stability, low conductivity, and unsatisfactory charge‐discharge (CD) rate performance. In this study, a novel approach is employed to address the drawbacks of MoS 2 . Carbon polymer dots (CPDs) are incorporated to prepare three‐dimensional (3D) nanoflower‐like spheres of MoS 2 @CPDs through the self‐assembly of MoS 2 2D nanosheets, followed by annealing at 700 °C. The CPDs play a main role in the creation of the nanoflower‐like spheres and also mitigate the MoS 2 nanosheet limitations. The nanoflower‐like spheres minimize volume changes during cycling and improve the rate performance, leading to exceptional rate performance and cycling stability in both Lithium‐ion and Sodium‐ion batteries (LIBs and SIBs). The optimized MoS 2 @CPDs‐2 electrode achieves a superb capacity of 583.4 mA h g −1 at high current density (5 A g −1 ) after 1000 cycles in LIBs, and the capacity remaining of 302.8 mA h g −1 after 500 cycles at 5 A g −1 in SIBs. Additionally, the full cell of LIBs/SIBs exhibits high capacity and good cycling stability, demonstrating its potential for practical application in fast‐charging and high‐energy storage.