Rationally designed hierarchical N, P co-doped carbon connected 1T/2H-MoS2 heterostructures with cooperative effect as ultrafast and durable anode materials for efficient sodium storage

Abstract MoS2 has attracted great attentions due to the high capacity and layered crystal structure. Whereas the intrinsic poor conductivity and big volume change of common used 2H-MoS2 bring about poor rate capability and bad cycling performance. Herein, three-dimensional N, P co-doped carbon network modified mixed phases of 1T/2H-MoS2 heterostructures (1T/2H-MoS2@PNC) have been rationally fabricated through a facile three-step strategy. Dependent on the cooperate effect of 1T/2H-MoS2 heterostructure and N, P co-doped carbon network, the 1T/2H-MoS2@PNC exhibits a high reversible capacity (475 mAh g-1 at 0.5 A g-1), outstanding rate capability (347 mAh g-1 at 10 A g-1) and long-term cyclic life up to 1000 cycles without capacity loss, obviously superior to 1T/2H-MoS2@PNC with different carbon contents/synthesis temperatures, 2H-MoS2@PNC and 1T/2H-MoS2@NC. Reaction kinetics and theoretical calculation have been investigated to verify the synergetic advantages of 1T/2H-MoS2 and N, P co-doping of carbon networks. Moreover, various ex-situ techniques have been employed to disclose the reaction mechanism of 1T/2H-MoS2@PNC. The assembled Na3V2(PO4)3//1T/2H-MoS2@PNC full batteries also demonstrate good electrochemical properties (a discharge capacity of 216 mAh g-1 over 300 cycles at 0.5 A g-1). All the results manifest the prospective application of 1T/2H-MoS2@PNC as high-performance anode materials for large-scale energy storage.