Synthesis of activated carbon from black liquor for the application of supercapacitor

Abstract In this present study, the black liquor carbonization has been investigated by hydrothermal process. The activated carbon from the carbonization of black liquor (AC-BL) and biomass based activated carbon from citrus sinensis flavedos (AC-OP) has been investigated for the suitability in supercapacitor application. The study have analysed in electrochemical measurement of both AC-BL and AC-OP in electrochemical station. The role of stable hydroxyl molecules on the surface of carbon material has been observed and its effective conductivity is studied. The superior performance of AC-OP derived nano porous carbon has fast ionic and electronic diffusion of the electrolyte in and out of the pores during charging and discharging due to high surface area. AC-BL exhibited with an EDLC mechanism, but AC-OP shows the pseudo capacitance property. The porous structure and oxygen doping characteristics in AC-BL can influence the potential electrode material for applications in the field of supercapacitors. With the help of this movement, electronic conductivity of the AC-BL has been increased. In general, electrochemical stability of the EDLC is far better than pseudo capacitor. From the EIS analysis, ESR value is very small for AC-BL (60 Ω), when compared to AC-OP (155 Ω). To conclude that the EIS results of low conductivity by AC-BL has potential to be future supercapacitor with enhanced treatment in carbonization techniques.