N/P co-doping regulates the local microcrystalline structure of hard carbon to facilitate sodium-ion storage

Abstract

To enhance the competitiveness of sodium-ion batteries in the field of energy storage, researchers have been committed to exploring optimization solutions for high-performance hard carbon anodes. However, there are many limitations to the improvement of hard carbon performance, making it difficult to achieve a simultaneous increase in slope capacity and plateau capacity. In this research, an exhaustive dissection was carried out on the mechanism through which N/P co-doped hard carbon anodes optimize the performance of sodium-ion batteries. The introduction of functional atoms promotes the generation of a large number of functional groups on the surface of hard carbon, providing more active sites for redox reactions and increasing the slope capacity. It is worth noting that N/P co-doping exhibits unique effects, effectively promoting the growth and bending of graphite like microcrystalline layers, thereby catalyzing the formation of closed pores and achieving a significant increase in plateau capacity. This research provides new research ideas for comprehensively improving the hard carbon capacity.