Synthesis of Manganese‐Based Prussian Blue Nanocubes with Organic Solvent as High‐Performance Anodes for Lithium‐Ion Batteries

Prussian blue analogue KxMnFe(CN)6·yH2O (m‐KMHCF) nanocubes with an average edge length of about 60 nm were synthesized by a simple hydrothermal reaction involving methanol. The microscopic size of m‐KMHCF nanocubes could be easily reduced to less than 100 nm as methanol was added to the reaction, over a long range of reaction temperatures and reaction times. As anode material for lithium‐ion batteries, the m‐KMHCF electrode delivered a high specific capacity of over 900 mAh g–1 at a current density of 100 mA g–1 after 50 cycles. In addition, it provided stable rate capability and lithium storage performance at the high current density of 382.3 mAh g–1 at 5000 mA g–1. It is worth noting that the capacity continued to rise during the galvanostatic charge‐discharge, and the specific capacity increased after charging and discharging at the large current. This phenomenon and the excellent electrochemical performance are mainly derived from the smaller microscopic size, which further led to crystal particle refinement during charge‐discharge. Prussian blue analogue KxMnFe(CN)6·yH2O (m‐KMHCF) nanocubes of size less than 100 nm were synthesized hydrothermally using methanol. As anode material for lithium‐ion batteries, the m‐KMHCF electrode delivered a high specific capacity of over 900 mAh g–1 at a current density of 100 mA g–1 after 50 cycles, as well as stable rate and lithium storage performance at a high current density of 382.3 mAh g–1 at 5000 mA g–1.