Potassium Hexafluorophosphate

• Catalog: OFC17084138
• CAS: 17084-13-8
• Category: Fluorinated Metal Phosphates
• Synonyms: Potassium fluophosphate
• Purity: >99%
• MDL Number: MFCD00011412

• IUPAC Name: potassium; hexafluorophosphate
• InChI: InChI=1S/F6P.K/c1-7(2,3,4,5)6;/q-1;+1
• InChI Key: YZDGRYDIGCWVND-UHFFFAOYSA-N
• Isomeric SMILES: F[P-](F)(F)(F)(F)F.[K+]
• Canonical SMILES: F[P-](F)(F)(F)(F)F.[K+]
• EC Number: 241-143-0

• Molecular Formula: F6KP
• Molecular Weight: 184.06
• Melting Point: 575 °C
• Density: 2.55-2.75 g/cm3
• Appearance: White powder or crystals
• Solubility: Soluble in water

• Hydrogen Bond Donor Count: 0
• Hydrogen Bond Acceptor Count: 7
• Rotatable Bond Count: 0
• Exact Mass: 183.927888
• Monoisotopic Mass: 183.927888
• Topological Polar Surface Area: 0Ų
• Heavy Atom Count: 8
• Formal Charge: 0
• Complexity: 67.1

Case Study

Potassium Hexafluorophosphate Enhances Electrochemical Performance in Anode-Free Lithium Metal Batteries

Teklay Mezgebe Hagos, et al. Electrochimica Acta, 2019, 316, 52-59.

Potassium hexafluorophosphate (KPF₆) has been demonstrated as an effective electrolyte additive for improving the electrochemical performance of anode-free lithium metal batteries (AFLMBs) with a Cu‖NMC cell configuration. When incorporated at 2 wt% in a commercial carbonate electrolyte (1 M LiPF₆-EC/DEC), KPF₆ significantly enhances charge/discharge capacity, coulombic efficiency, and capacity retention. Notably, AFLMBs with KPF₆ and tris(trimethylsilyl) phosphite (TMSP) additives retained 48% of their initial capacity after 20 cycles, compared to only 14% in cells without additives. The improved performance is attributed to the self-healing electrostatic shielding (SHES) effect of KPF₆, which mitigates dendrite growth, thereby enhancing battery stability and longevity. This study underscores the potential of KPF₆ as a crucial functional additive in next-generation lithium-metal-based energy storage systems.

Potassium Hexafluorophosphate (KPF6) Used for Interface Modification in High-Efficiency Perovskite Solar Cells

Wang Z, et al. Journal of Power Sources, 2021, 488, 229451.

Potassium hexafluorophosphate (KPF6) serves as a multifunctional interface modification material in perovskite solar cells (PSCs), significantly improving the device's performance by addressing interface defects. When applied between SnO2 quantum dots (QDs) and perovskite, KPF6 enhances carrier extraction and reduces charge recombination, which are critical for achieving high power conversion efficiencies (PCEs). The PF6- group in KPF6 forms strong hydrogen bonds with organic cations in perovskite, facilitating the re-orientation and redistribution of these cations, thereby optimizing the perovskite layer's structure. Simultaneously, KPF6 reacts with SnO2 QDs via ionic bonds between PF6- and Sn4+/Sn2+, effectively passivating interface defects at the SnO2 side. This dual-functionality suppresses non-radiative recombination and promotes electron transport, leading to a significant enhancement in the efficiency of the PSCs. Devices treated with 0.5 mg/ml KPF6 achieved a champion PCE exceeding 21% and retained approximately 90% of their initial PCE after 720 hours of storage in dry air. Thus, KPF6 plays a crucial role in boosting the performance and stability of PSCs, marking its importance as an interface material in high-efficiency solar cell applications.

Potassium Hexafluorophosphate as an Additive in Polyethylene Oxide-Based Solid Polymer Electrolytes for Lithium Dendrite-Free ASSLMBs

Li J, et al. Electrochimica Acta, 2022, 429, 141061.

Potassium hexafluorophosphate (KPF6) is utilized as a key additive in polyethylene oxide (PEO)-based solid polymer electrolytes (SPEs) for lithium dendrite-free all-solid-state lithium metal batteries (ASSLMBs). In this application, KPF6 enhances the dissociation of lithium salts, promoting the availability of free Li+ ions, which results in improved ionic conductivity of the solid electrolyte. The incorporation of KPF6 also improves the mechanical properties of the SPEs, increasing flexibility and facilitating the formation of a robust solid electrolyte interphase (SEI) rich in Li2S and LiF. Additionally, the presence of potassium ions (K+) from KPF6 is hypothesized to act as a shield, inhibiting the growth of lithium dendrites, a common issue in lithium metal batteries. The synergistic effects of these enhancements-boosted ionic conductivity, enhanced mechanical flexibility, and dendrite growth inhibition-make KPF6 a valuable additive in advancing the performance and stability of ASSLMBs. This functional role of KPF6 significantly contributes to preventing lithium dendrite formation and reducing interfacial side reactions, thus extending the lifespan and efficiency of lithium-based batteries.

Potassium Hexafluorophosphate in the Synthesis of Crown Ether Complexes

Dapporto P, et al. Inorganica Chimica Acta, 1996, 252(1-2), 383-389.

Potassium hexafluorophosphate (KPF6) plays a pivotal role in the synthesis of crown ether complexes, particularly with dibenzo-18-crown-6. In a typical preparation, equimolar amounts of KPF6 and dibenzo-18-crown-6 are reacted in methanol under reflux conditions for 2-3 hours, with continuous stirring. The resulting solution is filtered, and the product is crystallized from methanol, followed by washing with cold methanol and drying under vacuum. The complex, formed between the crown ether and KPF6, is characterized by X-ray diffraction, highlighting its potential in material science, specifically in ion transport and molecular recognition applications.