Synthesis of tea dregs-derived 3D interconnected honeycomb-like porous activated carbon for supercapacitor applications

ABSTRACT

Biomass-derived porous activated carbon and their applications as supercapacitor (SC) electrode materials have gained immense research interest owing to their abundance, inexpensive, recyclable, etc. Herein, we report the synthesis of tea dregs-derived 3D interconnected honeycomb-like porous activated carbon (HCAC) via a simple, effective, and inexpensive method for SC applications. Tea dregs waste was activated using NaOH activation with different mass ratios of 1:3, 1:4, and 1:5 under a N₂ atmosphere at 800°C for 3.5 h. The scanning electron microscope, energy dispersive X-ray (EDX) spectroscopy, adsorption/desorption isotherm of N₂, X-ray diffraction (XRD), FT-IR, and cyclic voltammetry methods were employed to analyze surface morphology, elemental compositions, specific surface area, crystallographic feature, surface functional groups, and electrochemical behavior, respectively. The as-obtained HCAC-3 has a 3D interconnected honeycomb-like porous architecture with high carbon and oxygen contents, achieved the specific surface area of 624 m²/g, amorphous carbon structure, and containing oxygen functional group. The symmetrical SC devices have an optimum specific capacitance of 100 F/g with an optimum energy density of 13.89 Wh/kg at a power density of 50.05 W/kg. This study could provide a good reference for the synthesis of biomass-derived 3D interconnected HCAC and its applications in energy storage devices systems, catalysts, and adsorbents.

KEYWORDS:

• Tea dregs waste
• 3D interconnected honeycomb-like porous architecture
• porous activated carbon
• electrode materials
• supercapacitor

Acknowledgements

The authors gratefully acknowledge to the Materials Physics and Nanotechnology Laboratory, Universitas Riau for providing a furnace, hydraulic press, and CV measurement for our work.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Notes on contributors

Eldya Mossfika

Mrs. Eldya Mossfika is a lecturer at the Department of Pharmacy, Faculty of Health Sciences, University of West Sumatra, Indonesia. She received her Master’s degree in Chemistry from Andalas University in 2020. Currently, she teaches Organic Chemistry, Qualitative Pharmaceutical Chemistry, Quantitative Pharmaceutical Chemistry, and Physicochemical Analysis for undergraduate students.

Hermansyah Aziz

Hermansyah Aziz is a lecturer and professor at the Department of Chemistry, Faculty of Mathematics and Natural Sciences, Andalas University, Indonesia. He received his P.hD degree in Physical Chemistry from Institut National Polytechnique de Lorraine, France in 1990. His research focuses on the technology of energy storage system, especially dye-sensitized solar cell, supercapacitor other energy-related applications.

Syukri Syukri

Dr. Syukri Syukri is a lecturer at the Department of Chemistry, Faculty of Mathematics and Natural Sciences, Andalas University, Indonesia. He received his P.hD degree in Inorganic Chemistry from Technische Universitaet Muenchen in 2007. His research focuses on the Inorganic Catalyst.

Agustino Agustino

Mr. Agustino Agustino is a a researcher assistant at the Material Physics and Nanotechnology Laboratory, Faculty of Mathematics and Natural Sciences, University of Riau. He received his Master’s degree in Material Physics from University of Riau in 2020.