Lithium tert-butoxideCAS #: 1907-33-1

Synonyms

 Lithium t-butoxide; Lithium 2-methylpropan-2-olate; Tert-Butoxylithium; Lithium tert-butylate; Tert-Butyl alcohol, lithium salt

Compound Formula: C4H9LiO 

Molecular Weight: 80.05 

Appearance: White to off-white powder or chunks 

Melting Point: N/A 

Boiling Point: N/A 

Density: 0.89 g/cm3 

Solubility in H2O: Reacts violently 

Exact Mass: 80.081344 g/mol 

Monoisotopic Mass: 80.081344 g/mol 

Charge: 0 

Sensitivity: Moisture sensitive; Hygroscopic

Product Introduction: Sodium Hexafluorophosphate (NaPF₆, CAS #: 1907-33-1)

Sodium hexafluorophosphate, denoted by the chemical formula NaPF₆ and CAS number 1907-33-1, is a pivotal inorganic salt that serves as a core electrolyte component in sodium-ion batteries (SIBs) and a range of sodium-based electrochemical systems. This white crystalline compound, composed of sodium cations (Na⁺) and hexafluorophosphate anions (PF₆⁻), is prized for its balanced set of properties—including high solubility in organic solvents, reliable ionic conductivity, and broad compatibility with electrode materials. As a cost-effective and well-characterized electrolyte salt, it plays a foundational role in advancing low-cost energy storage solutions that leverage sodium’s abundant natural reserves.

Chemical & Physical Properties

NaPF₆ exhibits key characteristics that make it a practical choice for sodium-based energy storage:

Solubility: Highly soluble in polar organic solvents such as ethylene carbonate (EC), dimethyl carbonate (DMC), and propylene carbonate (PC), enabling the formulation of electrolytes with concentrations up to 1.2 M. Its solubility in water is limited, but exposure to moisture can trigger partial hydrolysis.

Ionic Conductivity: Delivers moderate ionic conductivity (typically 3–6 mS/cm in optimized organic solvent blends), supporting efficient sodium-ion transport in SIBs and ensuring reliable battery performance.

Thermal Stability: Maintains structural stability up to approximately 170°C, though decomposition occurs at higher temperatures, releasing toxic phosphorus pentafluoride (PF₅) and sodium fluoride (NaF). This necessitates careful thermal management in high-temperature applications.

Electrochemical Window: Offers a stable electrochemical window of up to 4.4 V vs. Na⁺/Na, making it compatible with common SIB cathodes, including Prussian blue analogs, sodium nickel manganese oxides (e.g., NaNi₀.₅Mn₀.₅O₂), and sodium iron phosphate (NaFePO₄).

Hygroscopicity: Moderately hygroscopic, meaning it absorbs moisture from the air, which can lead to hydrolysis and the formation of corrosive hydrofluoric acid (HF). This reactivity underscores the need for strict moisture control during storage and handling.

Key Applications

Sodium hexafluorophosphate (CAS 1907-33-1) is widely utilized in sodium-based electrochemical technologies:

Sodium-Ion Batteries (SIBs): Acts as a primary electrolyte salt in both research and commercial SIBs, particularly in systems designed for grid energy storage, renewable energy integration, and low-cost stationary applications. Its balance of conductivity and affordability makes it a benchmark for evaluating new electrolyte formulations.

Electrolyte Blends: Often blended with advanced sodium salts (e.g., sodium bis(fluorosulfonyl)imide, NaFSI) to mitigate hydrolysis, reduce HF formation, and enhance cycle life. These blends improve stability in high-voltage SIBs and extend battery lifespan.

Sodium-Based Supercapacitors: Used in electrolytes for sodium-ion supercapacitors, where its ionic conductivity contributes to high power density and rapid charge-discharge capabilities, suitable for short-duration energy storage and power delivery.

Electrochemical Research: Serves as a reference electrolyte in studies of sodium-based electrode materials, providing a consistent baseline for evaluating the performance of new cathodes, anodes, and electrolyte additives.

Advantages & Limitations

NaPF₆ offers distinct benefits alongside important considerations:

Cost-Effectiveness: More affordable than specialty sodium salts like sodium bis(trifluoromethanesulfonyl)imide (NaTFSI), making it accessible for large-scale testing and early-stage commercialization of SIBs.

Established Performance: A well-studied material with predictable behavior, simplifying its integration into existing battery manufacturing processes and reducing development risks.

Broad Compatibility: Works with a wide range of SIB electrode materials, from hard carbon anodes to layered oxide cathodes, providing flexibility in battery design.

Limitations: Hydrolysis-induced HF formation can degrade electrode materials over time, limiting long-term cycle life. Its thermal stability is also inferior to newer salts like NaFSI, restricting use in high-temperature environments.

Synthesis & Quality Control

NaPF₆ is produced through controlled metathesis reactions:

Precursor Reaction: Sodium fluoride (NaF) reacts with phosphorus pentafluoride (PF₅) in an anhydrous organic solvent (e.g., acetonitrile or sulfur dioxide) under an inert atmosphere (e.g., nitrogen): NaF + PF₅ → NaPF₆.

Purification: The crude product undergoes recrystallization from anhydrous solvents to remove unreacted precursors and impurities. Drying under vacuum further reduces moisture content, ensuring high purity.

Quality control measures include ion chromatography (IC) to verify anion purity, inductively coupled plasma mass spectrometry (ICP-MS) for trace metal analysis, and Karl Fischer titration to confirm moisture levels (typically <30 ppm). Battery-grade NaPF₆ achieves purity levels of 99.9% or higher.

Safety & Handling

Proper handling of NaPF₆ is critical due to its reactivity and toxicity risks:

Moisture Control: Store in hermetically sealed containers under an inert atmosphere (e.g., nitrogen) to prevent hydrolysis. Use in dry environments, such as glove boxes, and avoid contact with water or humid air.

Toxicity: Hydrolysis and thermal decomposition products (HF, PF₅) are highly corrosive and toxic, causing severe skin, eye, and respiratory damage. Wear chemical-resistant gloves, goggles, and a respirator when handling, and work in well-ventilated areas.

Thermal Hazards: Avoid exposure to high temperatures (>170°C) to prevent decomposition. Keep away from open flames, strong oxidizers, and reducing agents.

Disposal: Dispose of waste and contaminated materials in accordance with local regulations for fluoride and phosphorus compounds, ensuring proper containment to prevent environmental contamination.

Refer to the product’s Safety Data Sheet (SDS) for detailed safety protocols and emergency response guidelines.

Packaging & Availability

NaPF₆ is available in formats tailored to research and industrial needs:

Crystalline Powder: Packaged in moisture-resistant aluminum bags (100g–10kg) with inert gas purging to minimize moisture absorption.

Pre-Dissolved Solutions: Available as ready-to-use solutions in organic solvent blends (e.g., EC/DMC) for immediate integration into electrolyte formulations, packaged in sealed 1L–20L containers.

Bulk quantities (50kg+ drums) are available for industrial-scale SIB production. Custom purities and low-moisture grades can be provided for specialized applications.

For technical specifications, pricing, or sample requests, contact our sales team, which specializes in electrolyte materials for sodium-based energy storage systems.

Health & Safety Information

 Signal Word: Danger 

Hazard Statements: H251-H302-H314 

Hazard Codes: F, C 

Precautionary Statements: P235-P260-P280-P301+P312-P303+P361+P353-P305+P351+P338 

Risk Codes: N/A 

Safety Statements: N/A 

RTECS Number: UB8520000 

Transport Information: UN 3206 8(4.2) / PG II 

WGK Germany: 3 

GHS Pictogram: Image,Image,Image

Chemical Identifiers

 Linear Formula: (CH3)3COLi 

Pubchem CID: 23664764 

MDL Number: FCD00050479 

EC No.: 217-611-5 

IUPAC Name: lithium; 2-methylpropan-2-olate 

Beilstein/Reaxys No.: 3620018 

SMILES: [Li+].CC(C)(C)[O-] 

InchI Identifier: InChI=1S/C4H9O.Li/c1-4(2,3)5;/h1-3H3;/q-1;+1 

InchI Key: LZWQNOHZMQIFBX-UHFFFAOYSA-N

Packing of Standard Packing: 

Typical bulk packaging includes palletized plastic 5 gallon/25 kg. pails, fiber and steel drums to 1 ton super sacks in full container (FCL) or truck load (T/L) quantities. Research and sample quantities and hygroscopic, oxidizing or other air sensitive materials may be packaged under argon or vacuum. Solutions are packaged in polypropylene, plastic or glass jars up to palletized 735 gallon liquid totes Special package is available on request.