Synthesis of Nanocarbon from Waste Engine Oil via Solution Plasma Process for Lithium-Ion Battery Anodes

Abstract

With the increasing demand for sustainable energy storage materials, the conversion of waste engine oil into functional carbon materials has attracted considerable attention due to its dual benefits of environmental remediation and value-added material production. In this study, nanocarbon materials were directly synthesized from waste engine oil via a solution plasma process under room temperature and atmospheric pressure conditions. The as-synthesized materials were systematically characterized using SEM-EDS, TEM, Raman spectroscopy, and X-ray diffraction (XRD), while their electrochemical properties were evaluated by cyclic voltammetry (CV), galvanostatic charge–discharge (GCD), and electrochemical impedance spectroscopy (EIS). The results revealed that the obtained nanocarbon partially graphitized outer layers surrounding amorphous carbon domains with particle sizes ranging from approximately 20 to 50 nm. The material exhibited typical electrochemical behavior of carbonaceous anodes for lithium-ion batteries, delivering a specific capacity of approximately 250 mAh.g-1 at a current density of 100 mA.g-1 and maintaining stable cycling performance over 200 charge-discharge cycles.