Preparation and Characterization of Physically Activated Carbon and Its Energetic Application for All-Solid-State Supercapacitors: A Case Study
Aziz Ahmad, M.A. Gondal, Muhammad Hassan, Rashid Iqbal, Sami Ullah, Atif Saeed Alzahrani, Waqar Ali Memon, Fazal Mabood, Saad Melhi
Abstract
High Resolution Image Download MS PowerPoint Slide Biomass-derived activated carbons have gained significant attention as electrode materials for supercapacitors (SCs) due to their renewability, low-cost, and ready availability. In this work, we have derived physically activated carbon from date seed biomass as symmetric electrodes and PVA/KOH has been used as a gel polymer electrolyte for all-solid-state SCs. Initially, the date seed biomass was carbonized at 600 °C (C-600) and then it was used to obtain physically activated carbon through CO 2 activation at 850 °C (C-850). The SEM and TEM images of C-850 displayed its porous, flaky, and multilayer type morphologies. The fabricated electrodes from C-850 with PVA/KOH electrolytes showed the best electrochemical performances in SCs (Lu et al. Energy Environ. Sci., 2014, 7, 2160) application. Cyclic voltammetry was performed from 5 to 100 mV s –1, illustrating an electric double layer behavior. The C-850 electrode delivered a specific capacitance of 138.12 F g –1 at 5 mV s –1, whereas it retained 16 F g –1 capacitance at 100 mV s –1 . Our assembled all-solid-state SCs exhibit an energy density of 9.6 Wh kg –1 with a power density of 87.86 W kg –1 . The internal and charge transfer resistances of the assembled SCs were 0.54 and 17.86 Ω, respectively. These innovative findings provide a universal and KOH-free activation process for the synthesis of physically activated carbon for all solid-state SCs applications.