Facile synthesis of hollow Cu_(3)P for sodium-ion batteries anode

摘要

Combining metal to form metal phosphide is a promising strategy to address the fast capacity decay of P rooted from its low electronic conductivity and large volume changes upon cycling. Cu_(3)P, which possesses a high theoretical gravimetric and volumetric capacity of 363 m Ahág^(-1) and 1028 AháL^(-1) and reasonable volume expansion of 156% during sodiation, was investigated as anode material in SIBs. Hollow-structured Cu_(3)P electrode delivers an initial de-sodiation capacity of * 159.0 m Ahág^(-1) with high capacity retention of ~85.1% over 50 cycles at 0.2 C rate and exhibits good rate performance,retaining 70% of the capacity when the current density increases from 0.2 C to 1.6 C. A 3 V-class full cell consisting of P2-Na_(2/3) Ni_(1/3) Mn_(1/2) Ti_(1/6)O_(2) cathode and Cu_(3)P anode was also assembled, which could achieve an energy density of ~189.3 Whákg^(-1)(based on the mass of both electrode materials) and average discharge voltage of~2.91 V when cycled in 1.0-4.3 V at 0.1C.