PREPARATION OF SELF-SULFUR-DOPED ACTIVATED CARBON FROM PETROLEUM COKE FOR ELECTROCHEMICAL ENERGY STORAGE

Due to recent technological developments, energy demands are rising with time. Renewable energy resources provide a considerable alternative to meet global energy demands. But due to its time-dependent operations, a robust storage system is required, which can store vast amounts of energy in a short time. Energy storage has earned a key position in energy devices due to its viability compared to energy harvesting devices. Also, in the last few decades, energy crises forced scientists and researchers to search for novel materials that may have the potential for energy harvesting and storage devices. In this regard, supercapacitors (SCs) based on carbon materials have recently received tremendous attention. A SC is an energy storage device with high energy and high-power densities and can be completely charged in seconds. By carefully selecting electrode materials and using cost-effective and simple preparation methods, SCs can be developed to store renewable energy on a larger scale. Specifically, sulfur-doped activated carbon (SAC) has remained a suitable electrode material for developing efficient SCs with high specific energy and specific power combined with low self-discharging. However, low yield AC due to low carbon content and external sulfur doping cause their high price. Therefore, a byproduct of oil refining, petroleum coke with a high carbon and sulfur content (~90 wt.%), could be considered an excellent raw material for the facile synthesis of sulfur-doped AC with a high yield. Here, we present a high-yield synthetic strategy to prepare highly porous petroleum coke-derived SAC (PCSAC). Following a comprehensive characterization of the prepared PCSAC, using X-ray diffraction, Raman spectroscopy, field emission scanning electron microscopy, X-ray photoelectron spectroscopy, thermogravimetry & differential scanning calorimetry, and Brunauer-Emmett-Teller analysis, its electrochemical performance as electrodes of the SC is investigated. The SAC-based symmetric SC's electrochemical performance exhibited a high specific capacitance with low equivalent series resistance and good energy and power densities. The fabricated PCSAC-based SC also shows high stability and Coulombic efficiency.