A Simple Chemical Processing Route in Order to Obtain High Purity Graphene

Graphene is one of the universal materials where it is the thinnest and can be the most robust material. Graphene has a high surface area, good conductivity and high mechanical strength where can be used in various applications. This study was used chemical vapour deposition (CVD) as the method to grown the graphene. Nickel foam was used as the template during the CVD process. However, the presence of Ni itself may reduce the purity of the grown graphene. Therefore, removing the grown graphene from the Ni template is needed. It also becomes a crucial part without lowering the purity of the grown graphene itself. A few reported works used chemical etching as the method to remove the Ni template. However, extra precaution is needed due to the use of heat and a high concentration of acid. Besides, multiple steps are required and a longer time is required due to get the free-standing graphene. Therefore, this study proposed using only a single step method where diluted HCL with ratio 1:1 was used as the etchant. Besides, this study also focused on varying the etching time between 6, 12 and 18 hours. As shown in Raman spectra, high purity of graphene was observed where G-band was high intensity compared to 2D-band. Besides, the XRD spectra show reducing the intensity of nickel peaks when prolonging the etching time. © 2023 American Institute of Physics Inc.. All rights reserved.