Speaker
Description
In the present work, we demonstrate a sustainable and cost-effective strategy for the synthesis
of highly capacitive activated carbon (AC) derived from bio-waste Kusha grass
(Desmostachya bipinnata) through a chemical treatment process followed by KOH
activation. The successful formation of few-layered activated carbon was systematically
confirmed using X-ray powder diffraction (XRD), transmission electron microscopy (TEM),
and Raman spectroscopy, revealing its structural and morphological characteristics.
Furthermore, the chemical bonding environment and functional groups present in the as-
prepared material were analyzed using Fourier transform infrared (FTIR) spectroscopy and
UV–visible spectroscopy. The surface area, pore size distribution, and porosity of the
synthesized AC were evaluated using the Brunauer–Emmett–Teller (BET) method, indicating
a highly porous structure favorable for electrochemical applications.
The electrochemical performance of the synthesized activated carbon was investigated using
cyclic voltammetry (CV) and galvanostatic charge–discharge (GCD) techniques, with
primary emphasis on GCD measurements due to their greater reliability and accuracy for
evaluating capacitive behavior. The as-synthesized AC electrode delivered a high maximum
specific capacitance of 218 F g⁻¹ within a stable operating potential window ranging from
−0.35 to +0.45 V. In addition, the electrode exhibited an impressive energy density of
approximately 19.3 Wh kg⁻¹ and a power density of around 277.92 W kg⁻¹ within the same
voltage range.
Moreover, the activated carbon electrode demonstrated excellent electrochemical stability,
retaining a substantial fraction of its initial capacitance even after 5000 charge–discharge
cycles. The fabricated supercapacitor device also maintained high energy and power densities
at increased charge–discharge rates, highlighting its robust rate capability and superior
cycling stability. These outstanding electrochemical properties can be attributed to the
optimized porous architecture, large surface area, and efficient ion transport pathways of the
Kusha grass–derived activated carbon.
Consequently, the bio-waste Kusha grass–derived activated carbon (DP-AC) emerges as a
highly promising electrode material for next-generation supercapacitor applications. This
study not only presents a simple and innovative approach for converting agricultural bio-
waste into high-value carbon materials but also underscores its significant potential for large-
scale implementation in electrochemical energy storage systems. We envision that this
sustainable synthesis route will contribute to the development of eco-friendly and high-
performance electrode materials, thereby expanding their practical applicability in advanced
energy storage technologies.