Enhancing sodium-ion battery performance with MXene@CoSe2/ZnSe@NC 0D 2D micro-/nanostructures

The groundbreaking development of 0D2D micro-/nanostructure hybrids, exemplified by MXene@CoSe2/ZnSe@NC, revolutionizes sodium-ion battery technology. Through precise carbonization and selenization processes, heterogeneous MXene@ZIF-8/ZIF-67 precursors are transformed into this novel hybrid, offering unparalleled sodium storage capability. The unique 0D2D architecture, characterized by the robust synergy between MXene and CoSe2/ZnSe@NC, ensures the even distribution of CoSe2/ZnSe@NC particles across MXene 2D nanosheets. This innovative 0D2D architecture results in remarkable electrochemical performance. Long-term cycling reveals an unprecedented 1.6 % average capacity decline per cycle after 3000 cycles at 20.0 A·g−1, with the cell still retaining a reversible capacity of 221 mAh·g−1, outperforming CoSe2@NC and CoSe2/ZnSe@NC. Electrochemical impedance spectra indicate significantly low charge transfer resistance of MXene@CoSe2/ZnSe@NC, resulting in rapid charge transfer and sodium ion diffusion. Furthermore, SEM analysis confirms the 0D2D architecture's critical role in maintaining structural integrity and preventing agglomeration. Ex-situ XRD and RAMAN data elucidate the CoSe2/ZnSe@NC nanoparticles' pivotal role in the sodium storage mechanism. This exceptional sodium storage technology was extended to full battery to underscore its practicality. In an NTO||MXene@CoSe2/ZnSe@NC full cell, MXene@CoSe2/ZnSe@NC exhibits impressive cycling stability, retaining 73.6 % of its initial capacity after 500 cycles at 3 A·g−1. In conclusion, the synthesized 0D2D micro-/nanostructure, MXene@CoSe2/ZnSe@NC represents a groundbreaking advancement in sodium-ion battery technology with a versatile application potential that transcends traditional limitations.