Effect of the Particles Morphology on the Electrochemical Performance of Na3V2(PO4)2F3‐yOy. Issue 1 (28th October 2021)

• Record Type: Journal Article
• Authors: Fang, Runhe; Olchowka, Jacob; Pablos, Chloé; Camacho, Paula Sanz; Carlier, Dany; Croguennec, Laurence; Cassaignon, Sophie
• Is Part Of: Batteries & supercaps. Volume 5:Issue 1(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-10-28
• Subjects: morphology design -- Na-ion batteries -- Na3V2(PO4)2F3 -- Na3(VO)2(PO4)2F -- polyanions -- synthesis design; Electrochemistry -- Periodicals; Electrodes -- Periodicals; Electric batteries -- Periodicals; 621.31242
• DOI: 10.1002/batt.202100179
• Languages: English
• ISSNs: 2566-6223

Abstract

Abstract: Among all the positive electrode materials explored for Na‐ion batteries, the family of Na3 V III 2‐ y (V IV O) y (PO4 )2 F3‐ y (NVPFO y ) has attracted extensive attention for its high operating voltage and structural stability. In order to promote better performance at high rates, it appears interesting to consider the correlation between NVPFO y 's composition, morphology (size and shape) and electrochemical properties. Here, solvothermal syntheses were considered in order to obtain a series of NVPFO y compounds showing different morphologies (such as nanospheres, flakes, cylindrical aggregates or desert‐roses) by playing on different synthesis parameters like water/ethanol ratio, stoichiometry of the precursors' mixture, heating rate, and the presence or not of a surfactant. Four compounds presenting different morphology have been fully characterized by X‐ray diffraction, scanning electron microscopy, transmission electron microscopy, infrared, NMR and XPS spectroscopies. Their electrochemical properties are studied using electrodes rich in active material in order to better observe the influence of the morphology on the energy storage performance and are compared to those of Na3 V2 (PO4 )2 F3 and Na3 V2 (PO4 )2 FO2 reference materials obtained by solid‐state synthesis and with shapeless morphology. Abstract : Particle's morphology control : A series of Na3 V III 2‐ y (V IV O) y (PO4 )2 F3‐ y materials is synthesized with various morphologies in order to investigate the morphology's impact on high rate electrochemical performance.