Poly (Vinyl Alcohol)/Agar Hydrogel Electrolytes Based Flexible All-in-One Supercapacitors with Conducting Polyaniline/Polypyrrole Electrodes

Khadija Hasan; Shahid Bashir; Ramesh Subramaniam; Ramesh Kasi; Kashif Kamran; Javed Iqbal; Hamed Algarni; Abdullah G Al-Sehemi; S Wageh; M Pershaanaa; Fathiah Kamarulazam

doi:10.3390/polym14214784

Poly (Vinyl Alcohol)/Agar Hydrogel Electrolytes Based Flexible All-in-One Supercapacitors with Conducting Polyaniline/Polypyrrole Electrodes

Polymers (Basel). 2022 Nov 7;14(21):4784. doi: 10.3390/polym14214784.

Authors

Khadija Hasan¹, Shahid Bashir², Ramesh Subramaniam¹, Ramesh Kasi¹, Kashif Kamran³, Javed Iqbal⁴, Hamed Algarni^{5

6}, Abdullah G Al-Sehemi^{5

7}, S Wageh^{8

9}, M Pershaanaa¹, Fathiah Kamarulazam¹

Affiliations

¹ Centre for Ionics Universiti Malaya, Department of Physics, Faculty of Science, Universiti Malaya, Kuala Lumpur 50603, Malaysia.
² Higher Institution Centre of Excellence (HICoE), UM Power Energy Dedicated Advanced Centre (UMPEDAC), Level 4, Wisma R&D, Universiti Malaya, Jalan Pantai Baharu, Kuala Lumpur 59990, Malaysia.
³ Department of Physics, University of Agriculture, Faisalabad 38040, Pakistan.
⁴ Center of Nanotechnology, King Abdulaziz University, Jeddah 21589, Saudi Arabia.
⁵ Research Center for Advanced Materials Science (RCAMS), King Khalid University, P.O. Box 9004, Abha 61413, Saudi Arabia.
⁶ Department of Physics, Faculty of Science, King Khalid University, P.O. Box 9004, Abha 61413, Saudi Arabia.
⁷ Department of Chemistry, College of Science, King Khalid University, P.O. Box 9004, Abha 61413, Saudi Arabia.
⁸ Department of Physics, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia.
⁹ K. A. CARE Energy Research and Innovation Center, King Abdulaziz University, Jeddah 21589, Saudi Arabia.

Abstract

The major components of supercapacitor are electrodes and electrolytes which are fabricated using various materials and methods. Hydrogel is one such material that is used in supercapacitors as electrodes and electrolytes or both. Hydrogels are usually described as a soft and porous network of polymer materials that can swell in water because of the hydrophilic nature of its polymer chains, compriseng a 3D structure. It is well known that supercapacitors possess high-power density but low energy density. For enhancing energy density of these electrochemical cells and a boost in its electrochemical performance and specific capacity, binder free conducting polymer hydrogel electrodes have gained immense attention, especially polyaniline (PANI) and polypyrrole (PPy). Therefore, in this work, chemically crosslinked PVA/Agar hydrogel electrolytes have been prepared and employed. Agar has been added in PVA since it is environmentally friendly, biodegradable, and cost-effective natural polymer. Subsequently, the binder free polyaniline/polypyrrole electrodes were grown on the PVA/Agar hydrogel electrolytes to fabricate all-in-one flexible hydrogels. The synthesized hydrogels were characterized using X-ray diffraction (XRD) analysis, Fourier transform infrared (FTIR) analysis, Field emission scanning electron microscope (FESEM) and mechanical studies. Then, the all-in-one flexible supercapacitors were fabricated using the hydrogels. The electrochemical studies such cyclic voltammetry (CV), galvanic charge discharge (GCD), and electrochemical impedance spectroscopy (EIS) studies. The fabricated all-in-one lamination free supercapacitors showed promising results and by comparing all four samples, PAP2 where 5 mL of PVA was used in combination with 3 mL of Agar and 5 mL of PANI and PPy each, exhibited the highest areal capacitance of 750.13 mF/cm², energy density of 103.02 μWh/cm², and 497.22 μW/cm² power density. The cyclic stability study revealed the 149% capacity retention after 15,000 cycles.

Keywords: agar; all-in-one flexible hydrogel; conducting polymers; flexible; supercapacitors.

Grants and funding

Authors acknowledge support and funding of King Khalid University through Research Center for Advanced Materials Science (RCAMS) under grant no: RCAMS/KKU/007/21, and also, the Authors acknowledge the support provided by King Abdullah City for Atomic and Renewable Energy (K.A.CARE) under K.A.CARE-King Abdulaziz University Collaboration Program.