Electrochemical Studies on Tamarindus indica Fruit Shell Bio-Waste Derived Nanoporous Activated Carbons for Supercapacitor Applications

Abstract

<jats:p>Supercapacitors are perfect energy storage devices; they can be charged almost instantly and release energy over a long period. Another advantage of using supercapacitors is their multipletimes chargeable behavior with minimum degradation in performance. Herein, we report the nanoporous activated carbon based modified electrodes prepared by using phosphoric acid (PA) activation method at different temperatures (600, 700, 800, and 900 °C) using bio-waste precursor, <jats:italic>Tamarindus indica</jats:italic> (<jats:italic>T. indica</jats:italic>) fruit shell. Because of their excellent energy storage capacity, in the present work, supercapacitive behavior of the nanoporous activated carbon based modified electrode has been demonstrated and hence the electrochemical properties of the developed supercapacitor electrodes are analyzed using cyclic voltammetry, galvanostatic charge–discharge measurements, electrochemical impedance spectroscopy and cycling studies using 1 M KOH as the electrolyte. The developed supercapacitor nanoporous activated carbon materials are characterized by X-ray diffraction, functional group analysis, surface area and morphological studies.</jats:p>

A simple conversion of expired medicines into nontoxic activated carbon for energy storage applications

“…Because, at high scan rate as well as at high current density, the short time duration does not permit the completion of chemical reactions at the inner area of the active material, and the observed capacitance was contributed only from the F I G U R E 4 (A-C) FESEM images, (D) EDX analysis, and (E, F) TEM images of Em AC outer surface area of Em AC electrode material, that is, the ion diffusions that occurred at the electrode surface, prevented the migration of ions between electrode and electrolyte. 19,24,34 Further, Table 1 indicates that Em AC electrode exhibits a comparatively higher C sp value than the previously reported works. The electrode materials with much lower resistance are essential for power device fabrication.…”

“…With the aid of three electrode system, the specific capacitance (C sp ) values of Em AC@Ni foil electrode were calculated from Equations ( 1) and ( 2), respectively, from CV and GCD. 16,24…”

“…In addition, activated carbon could provide a high surface area with pronounced porous structure, which could aid for enhanced specific capacitance through the formation of electrostatic double layer. 24,25 In particular, biowaste or biomass-derived activated carbon attracted intense focus for SC applications because of its cost effectiveness and abundance. [26][27][28][29][30][31] Moreover, biowaste-derived activated can become an alternate source for the petrochemical feedstocks, particularly for energy generation.…”

Surface and Diffusion Charge Contribution Studies of Human Hair-Derived Heteroatom-Doped Porous Carbon Electrodes for Supercapacitors

“…The presence of the carbonyl group was corroborated by the peak positioned at 1634 cm –1 . The overlapping of C–O stretching vibrations is represented by a small peak at 1380 cm –1 , whereas the CO stretching vibrations are represented by a broad peak at 1115 cm –1 . , …”

“…The overlapping of C−O stretching vibrations is represented by a small peak at 1380 cm −1 , whereas the CO stretching vibrations are represented by a broad peak at 1115 cm −1 . 24,25 Barrett−Joyner−Halenda (BJH) pore size distribution and BET N 2 adsorption−desorption studies were used to evaluate the SSA as well as for the assessment of the various pores present and their allocations in the as-generated AC. Figure 3a displays the N 2 adsorption−desorption isotherm of the samples which clearly reveals the typical type IV (mesoporous characteristics) and type II (macroporous characteristic) adsorption−desorption behaviors.…”