Studies on enhanced negative electrode performance of boron-treated pistachio shell-derived hard carbon in Na-ion battery

Due to its abundant and inexpensive availability, sodium has been considered for powering batteries instead of lithium; hence; sodium-ion batteries are proposed as replacements for lithium-ion batteries. New types of negative electrodes that are carbon-based are studied to improve the electrochemical performance and cycle life of sodium cells. Although this area of research has gained minimal attention, prior research suggests that the approach is not suitable for commercial developments. We studied pistachio-derived hard carbon structure using Field Emission Scanning Electron Microscopy (FESEM), X-ray diffraction (XRD), and Raman Spectroscopy and concluded that it has a curly layered structure that may provide good electrochemical performance. This could lead to new uses for batteries in environmentally friendly electric vehicles and other situations. To enable improved Na⁺ storage and transport in Sodium-Ion Batteries (SIBs), a modified approach using the boron treatment strategy was used to simultaneously optimize and study electrochemical data like Cyclic Voltammetry (CV), Galvanostatic Charge- Discharge profiles (GCD profiles), and Electrochemical Impedance Spectroscopy (EIS) of pistachio curly hard carbon multi-layered structures, including curly layered morphology. Boric acid treatment etches the carbon surface, which creates micropores that lead to an increase in the overall surface area. The curly `pistachio-derived hard carbon (PHC) exhibits an initial capacity of 305 mAhg^− 1 at 0.05 Ag^− 1 with retention of 236 mAhg^− 1 after 100 cycles, whereas a good initial capacity of 348 mAhg^− 1 at 0.05 Ag^− 1 with retention of 285 mAhg^− 1 after 100 cycles is observed in boron-treated pistachio-derived hard carbon (BPHC). Boron-treated pistachio shell-derived hard carbon electrode shows high capacity, ultra-long cycling stability, as well as high-rate capability.