Enhanced supercapacitor materials from pyrolyzed algae and graphene composites

Abstract

This study focuses on the synthesis and characterization of supercapacitor materials derived from pyrolyzed natural compounds. Four compounds were investigated: methylcellulose with lysine (ML), methylcellulose with lysine-graphene composite (MLG), algae (A), and algae-graphene composite (AG). The pyrolysis process was utilized to convert these natural compounds into carbon-based materials suitable for supercapacitor applications. The properties of the resulting materials were analyzed extensively to evaluate their potential as supercapacitor electrodes. The electrochemical performance, including specific capacitance, cyclic stability, and rate capability was measured using various characterization techniques. The effects of incorporating graphene into the lysine-methylcellulose and algae matrices were also studied to explore the enhancements in supercapacitor performance. In both cases, the addition of graphene resulted in a positive effect. Among all the materials investigated, the algae-graphene composite exhibited the most favorable properties, demonstrating a specific capacitance of 192 F g⁻¹ after 10,000 galvanostatic charge–discharge cycles at a current of 5 A g⁻¹ in K₂SO₄ electrolyte. This exceptional performance underscores the potential of the algae-graphene composite as a highly efficient and durable electrode material for supercapacitor applications.