Unveiling the potential of Na2FePO4F@PEG composite as cathode material for sodium-ion batteries

• Published in: Journal of molecular structure Vol. 1312; p. 138524
• Main Authors: El Kacemi, Zineb, Fkhar, Lahcen, El Maalam, Khadija, Aziam, Hasna, Ben Youcef, Hicham, Saadoune, Ismael, Ait Ali, Mustapha, Boschini, Frederic, Mahmoud, Abdelfattah, Mounkachi, Omar, Balli, Mohamed
• Format: Journal Article Web Resource
• Language: English
• Published: Elsevier B.V 15.09.2024
• Subjects: Analytical Chemistry; Carbon coating; Cathode; Cathodes material; Chemistry; Chimie; Cost-effective approach; Direct use; Electrochemical performance; Fluoro-phosphates; Fluorophosphate; Inorganic Chemistry; Organic Chemistry; Orthorhombic structures; Physical, chemical, mathematical & earth Sciences; Physique, chimie, mathématiques & sciences de la terre; Sodium ion batteries; Spectroscopy; Storage systems; Upscaling; Cathode; Carbon-coating; Sodium-ion batteries; Fluorophosphate
• DOI: 10.1016/j.molstruc.2024.138524
• ISSN: 0022-2860; 1872-8014

•The addition of PEG to Na2FePO4F enhances the Na extraction/insertion processes thereby improving electrochemical reactions.•The NaPF6/FEC electrolyte provides better electrochemical characteristics and high cycling stability as indicated by high coulombic efficiency and discharge capacities.•A 15 % PEG addition is considered optimal for improving electronic and electrochemical performance. The economic and environmental advantages of Na2FePO4F fluorophosphate have positioned it as a highly promising cathode material for sodium-ion batteries (SIBs). This recognition stems from its demonstrated potential to address key challenges in energy storage systems, making it a subject of extensive research and studies. In this paper, the preparation of Na2FePO4F powder through a simplified, upscaling, and cost-effective approach that involves the direct use of phosphoric acid is described, aiming to evaluate its electrochemical performance. The obtained orthorhombic structure (S.G. Pbcn) is mixed with varying percentages of polyethylene glycol as a carbon source (15% and 20%) to generate large specific surfaces, improve electronic conductivity, and achieve an optimized carbon content for these materials. The 15% and 20% PEG-coated Na2FePO4F are evaluated at a 2 - 4 V voltage range at C/15 in Na-half cells using two electrolyte formulations: 5% FEC 1 M NaClO4:PC and 1 M NaPF6:PC. The NaPF6/FEC electrolyte exhibits better electrochemical characteristics and high cycling stability, especially in the case of the 15% PEG-coated material. These findings are also supported by the data from differential plots and rate capabilities, highlighting the potential of the coated material for applications in high-performance energy storage applications.