Multidimensional Co‐Exfoliated Activated Graphene‐Based Carbon Hybrid for Supercapacitor Electrode

• Published in: Energy technology (Weinheim, Germany) Vol. 7; no. 10
• Main Authors: Phiri, Josphat, Gane, Patrick, Maloney, Thad C.
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 01-10-2019
• Subjects: Activated carbon; Biodegradability; Biodegradation; carbon hybrids; Cellulose; Electrochemical analysis; Electrochemistry; electrode; Electrode materials; Electrodes; Fabrication; Graphene; nano-microfibrillated cellulose; Porosity; Renewable resources; Supercapacitors; Surface area; Sustainable materials
• ISSN: 2194-4288; 2194-4296
• DOI: 10.1002/ente.201900578

Herein, a simple route for the fabrication of highly porous‐activated few‐layer graphene for application in supercapacitors as an electrode material is reported. The process makes use of natural and renewable materials, which is an essential prerequisite, especially for large‐scale application. Few‐layer graphene is exfoliated in aqueous suspension with the aid of microfibrillated cellulose (MFC), an environmentally benign eco‐friendly medium that is low‐cost, biodegradable, and sustainable. The exfoliated product is subsequently activated to increase the surface area and to form the desired pore structure. The prepared electrode materials exhibit a high surface area of up to 720 m2 g−1. MFC is also used as a nontoxic environmentally friendly binder in the electrode application. The electrochemical performance is evaluated in a three‐electrode system, and the prepared samples show a high specific capacitance of up to 120 F g−1 at a current density of 1 A g−1. The samples also exhibit a high capacity‐retention rate of about 99% after 5000 cycles and 97% after 10 000 cycles. The proposed method for the fabrication of graphene‐based supercapacitor electrode materials, based largely on renewable and sustainable materials, offers potential for commercially viable applications.
A simple method for the fabrication of graphene‐based hybrid electrodes for energy storage applications is presented. This method can serve as a route for the fabrication of high performance energy storage devices based largely on renewable and sustainable materials with a potential for large‐scale applications.