Single-crystalline Mn2V2O7 anodes with high rate and ultra-stable capability for sodium-ion batteries

The abundant sodium resources provide a great potential for the practical application of sodium ion bat-teries (SIBs). However, the development of feasible anode materials with high-rate capability to solve the slow diffusion kinetics of Na+ has always been a major challenge for high performance SIBs. Herein, a layer -structured metal vanadate Mn2V2O7 (MnVO) with large open channel within its crystal structure frame is for the first time identified as a promising candidate for high-rate SIB anodes, which ensures a large pseudocapacitance contribution. Moreover, the prepared micron size single crystal structure of MnVO ef-fectively shortens the diffusion and transmission paths of Na+ ions and electrons, thus accomplishing high capacity (a reversible capacity of 250 mA h g-1 at 0.2 A g-1), excellent cycling stability (125 mA h g-1 at 10 A g-1 after 3500 cycles with 98% capacity retention) and fast charge and discharge rates (120 mA h g-1 at 20 A g-1 after 5000 cycles). This work explores transition metal vanadates as SIB anodes with excellent rate performance.(c) 2022 Elsevier B.V. All rights reserved.

Automated summary

This study identifies a metal vanadate material with a large open channel structure, Mn2V2O7 (MnVO), as a promising candidate for high-rate sodium ion battery anodes. The prepared micron size single crystal structure effectively shortens the diffusion and transmission paths of sodium ions and electrons, resulting in high capacity, excellent cycling stability, and fast charge and discharge rates.