HARD CARBON BASED ON PHENOL FORMALDEHYDE RESIN AS AN ANODE MATERIAL FOR SODIUM ION BATTERIES

This work is devoted to the development of anode material for sodium-ion batteries. Non-graphitizable carbon as known as hard carbon is most often used as such a material in research, since, unlike the situation with the problematic intercalation of sodium ions into graphite, here they can intercalate into pseudographitic domains and be reversibly adsorbed on surface edges, defects and nano-sized pores. In this research, samples of material for the anodes of sodium-ion batteries based on hard carbon obtained by carbonization under different conditions of a resol-type phenol-formaldehyde resin with a molar ratio of reagents of 1:1 were prepared and studied. Two series of experiments were carried out on the synthesis of ten anode materials: in which the effect of carbonization temperature (1000/1100/1200/1400 °C) and the effect of exposure time at a temperature of 1100 °C (30/60/90/120/180/240 min) were studied. All obtained materials are subjected to grinding and sifting to obtain a powder with a particle size of no more than 80 μm. The manufactured materials were studied by transmission electron microscopy, scanning electron microscopy and Raman spectroscopy. As a result of electrochemical measurements, it was found that the carbonization temperature of phenol-formaldehyde resin greatly affects the discharge capacity of the final material, which increases to 311 mAh/g in the first cycle when moving from 1000 to 1100 °C and then decreases. On the other hand, the dependence of capacity on exposure time is also not monotonic and has a certain optimum around 180 min. In all cases, the Coulombic efficiency in the first cycle varies from 70 to 85% and exceeds 80% for the sample held for 180 min at the temperature of 1100 °C. For citation: Urvanov S.A., Nasraoui M., Filimonenkov I.S., Mordkovich V.Z. Hard carbon based on phenol formaldehyde resin as an anode material for sodium ion batteries. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2024. V. 67. N 10. P. 80-87. DOI: 10.6060/ivkkt.20246710.12y.