Prussian Blue@MoS2 Layer Composites as Highly Efficient Cathodes for Sodium‐ and Potassium‐Ion Batteries

Abstract Prussian blue (PB) represents a simple, economical, and eco‐friendly system as cathode material for sodium‐ion batteries (SIBs). However, structural problems usually worsen its experimental performance thus motivating the search for alternative synthetic strategies and the formation of composites that compensate these deficiencies. Herein, a straightforward approach for the preparation of PB/MoS 2 ‐based nanocomposites is presented. MoS 2 provides a 2D active support for the homogeneous nucleation of porous PB nanocrystals, which feature superior surface areas than those obtained by other methodologies, giving rise to a compact PB shell covering the full flake. The nanocomposite exhibits an excellent performance as cathode for SIBs with discharge capacity values up to 177 mA h g −1 and a specific capacitance of 354 F g −1 . These values are even larger for the intercalation of K + ions (up to 215 mA h g −1 , reaching a specific capacitance of 489 F g −1 ). Compared to similar composites, superior performance can be ascribed to a synergistic effect of the coordination compound with the 2D material.