Rationally constructing CoSe2/NiSe2@N-doped carbon heterostructures combined with CNTs for ultralong cycle life Na-ion batteries

The rising interest in heterostructure anode materials in recent years is attributed to their ability to decrease the activation energy of surface reactions by establishing a built-in electric field at the interface between different materials. This approach proves to be an effective strategy for significantly enhancing both capacity and overall performance. In this paper, a hybrid of CoSe2/NiSe2@N-doped carbon heterostructures with CNTs (CNS@NC/ CNTs) was synthesized using a simple wet chemical method in conjunction with the selenization process. The anode material, CNS@NC/CNTs, fabricated for use in Na-ion batteries (NIBs), shows outstanding rate capability attributed to the combined impact of bimetallic selenides and the interfacial properties of the heterostructure. Notably, it demonstrates exceptional performance, delivering a capacity of 530.2 mAh g- 1 at a current density of 0.5 A g- 1 , superior rate capability of 285.9 mAh g- 1 at 10 A g- 1 , and robust long-term cycling stability with 80 % capacity retention after 10,000 cycles at a high current density of 40 A g- 1 . Additionally, when utilized in a sodium-ion full cell alongside Na3V2(PO4)3 (NVP) as the cathode, the optimized configuration with CNS@NC/ CNTs as the anode continues to exhibit excellent performance. Specifically, it achieves a capacity of 309.7 mAh g- 1 enides integrated into heterostructures for enhancing the performance of NIBs. at 1 A g- 1 within the voltage range of 0.5 to 3.5 V. This study underscores the potential of bimetallic selenides integrated into heterostructures for enhancing the performance of NIBs.