Carbon-coated MoS2 nanosheets@CNTs-Ti3C2 MXene quaternary composite with the superior rate performance for sodium-ion batteries

The exploration of advanced MoS2-based electrode materials overcoming their inherent low conductivity and large volume changes is of importance for next-generation energy storage. In this work, we report a simple and high-efficient one-pot hydrothermal approach to prepare a unique and stable 1D/2D heterostructure. In the architecture, ultrathin carbon layer-coated MoS2 nanosheets with large expanded interlayer of 1.02 nm are vertically grown onto the Ti3C2 MXene and cross-linked carbon nanotubes (CNTs), giving rise to a highly conductive 3D network. The interlayer expanded MoS2 nanosheets can greatly facilitate the Na ions/electrons transmission. Meanwhile, the N-doped 1D/2D CNTs-Ti3C2 matrix can be used as a strong mechanical support to well relieve the large volume expansion upon cycles. As a combination result of several advantages, the developed quaternary C-MoS2/CNTs-Ti3C2 composite anode shows an excellent sodium storage performance (562 mA h g(-1) at 100 mA g(-1) after 200 cycles) and rate capability (475 mA h g(-1) at 2000 mA g(-1)). The density functional theory calculations further prove that the full combination of layer-expanded MoS2 nanosheets and N-doped Ti3C2 matrix can significantly enhance the adsorption energy of Na ions, further resulting in the enhancement of sodium storage capabilities. (C) 2022 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.