CHARACTERISATION OF GRAPHENE DERIVED FROM COCONUT SHELLS: IMPACT OF AMMONIA DOPING AND THE SONICATION METHOD

Abstract

Coconut shells, a type of biomass, are a potential carbon source. They can be transformed into charcoal via carbonisation, and then can be synthesised into graphene. As an eco-friendly and cost-effective material, it can be used to produce Graphene Nanosheets (GNS). The process involves roasting the coconut shells at 220 °C and pyrolysing at 600 °C to obtain pure GNS or GNS-NH3 doped. The material is then sieved using a 200-mesh sieve and sonicated. The graphene's morphology is examined using SEM-EDX tests and characterised by XRD and FTIR. Its electrical conductivity stability is assessed by measuring the current strength at voltages of 40, 44, 48, 51, and 55 Volts with a current of 17.6 Amperes. Graphene demonstrates relative stability, with a slight decrease in electron loss with small current increases, which helps control the electron mobility. This is due to graphene's capacity to store and slowly release electrons. The stability of graphene's conductivity aids in electric current conduction and extends the lifespan of graphene-based batteries. However, graphene exhibits better electrical conductivity at 40 V than at 55 V. The literature suggests that increasing the voltage results in decreased electrical conductivity. This is because GNS is not yet fully capable of controlling the electron mobility at higher voltages, making it less stable in accommodating the electrical conductivity.

Keywords

• coconut shell
• carbonisation
• pyrolysis
• sonication
• graphene nanosheet