Challenges of Using Natural Extracts as Graphene Oxide Reducing Agents (Brief Review)
Lia Destiarti (a), Riyanto (b), Roto (c), Mudasir (c*)

a) Department of Chemistry, Universitas Tanjungpura
Jalan Profesor Hadari Nawawi, Pontianak, 78124, Indonesia
b) Department of Chemistry, Universitas Islam Indonesia
Jalan Kaliurang Km 14,5, Sleman, Yogyakarta, 55584, Indonesia
c) Department of Chemistry, Universitas Gadjah Mada
Jalan Sekip Utara, Bulaksumur, Yogyakarta, 55281, Indonesia
*mudasir[at]ugm.ac.id

Abstract

Reduced graphene oxide attracts much attention because of its high thermal conductivity, electrical properties, Young^s modulus, high mechanical strength and optical transmittance, and theoretical areas. This material is widely used for various applications. The graphene oxide (GO) reduction process produces rGO. The most commonly used reducing agent is very toxic hydrazine. Multiple searches for more environmentally friendly reducing agents have been investigated to replace hydrazine. This brief review discusses the use of natural extracts as reducing agents. This section discusses several techniques for synthesizing GO into rGO in laboratory experiments. In addition, the chemical components and mechanism of the reduction process are also reviewed and compared with other reducers. In this section, some of the mechanisms offered by researchers are discussed concerning the chemical content of plant extracts. This review explains several fundamental characterization techniques such as UV-Vis, FTIR, XRD, and Raman. These main characterizations will be used to indicate the success of the reduction process so that initial screening can be carried out before a complete characterization is conducted. The developing natural reducing agents face some challenges, including the compounds^ complexity and the synthesis method^s reproducibility. This review summarizes the strategy for applying eco-friendly agents to reduce GO to rGO that can help the young researcher to find novel extract and use it effectively in the synthesis process. It can be concluded that the chemical compound with phenolic or amine in the extract is the suitable candidate to propose. The most important thing to emphasize is that the synthesis procedure involving the heating process is the most common for reducing GO to rGO. The combination of XRD and Raman is the tool that can be used as the primary characterization to make sure that rGO was obtained in the final product.

Keywords: Hydrazine, Plant extract, Raman, Reduced graphene oxide, XRD

Topic: Environmental Chemistry and Engineering