Prussian Green: A High Rate Capacity Cathode for Potassium Ion Batteries

Abstract

The influence of the precursors, namely potassium ferrocyanide and potassium ferricyanide on the particles sizes of Prussian Blue (PB) and Prussian Green (PG), under identical reaction conditions have been investigated. It was found that the particle sizes influence the gravimetric capacity utilization of these materials as cathodes for aqueous potassium (K +) ion batteries. The PG particle sizes were on the order of 50-75 nm, whereas PB particles size were on the order of 2-10 microns. The PG cathodes demonstrated a reversible capacity of 121.4 mAhr/g, with a coulombic efficiency of 98.7% compared to PB cathodes which demonstrated 53.8 mAhr/g, with a coulombic efficiency of 100%. We interpret the increased capacity of PG batteries relative to PB batteries as being a result of the smaller particle size of PG, which results in greater accessibility of the cathode to K+ ions.

A Fe/Mn‐Based Prussian Blue Analogue as a K‐Rich Cathode Material for Potassium‐Ion Batteries

“…Indeed Prussian blue analogues have mostly been evaluated as a NIB cathode material before the recent interest in KIBs, after Wessells et al . and Padigi et al . reported very stable cycling of Prussia blue in aqueous electrolyte.…”

Non-Aqueous K-Ion Battery Based on Layered K0.3MnO2and Hard Carbon/Carbon Black

“…9,10 Aqueous systems, comprising Prussian blue (KFe III Fe II (CN) 6 ) or other hexacyanoferrates as active material, have been studied intensively since the 1980s. [11][12][13][14][15] In addition, * Electrochemical Society Member. z E-mail: daniel.buchholz@kit.edu; stefano.passerini@kit.edu layered K x MnO 2 · (0.3 ≤ y ≤ 0.6) H 2 O has been reported as cathode material in aqueous K-ion capacitors.…”

Improved potassium ion storage performance of graphite by atomic layer deposition of aluminum oxide coatings

“…It indicated that K + intercalation has achieved. Also, the color of the electrode changes from dark gray to golden, which confirms the formation of KC 8 in the electrode …”

“…At present, the improvement of the cyclic stability of PIBs graphite‐based anode is a focus of attention. The dramatic volume expansion accompanied by K + insertion‐disinsertion reaction was one of the major causes of poor cycling performance . It is useful to improve the K + intercalation/delamination crystal gap of graphite and to establish an optimized nanostructure based on graphite to buffer the volume change.…”