Structure of Coal-Derived Metal-Supported Few-Layer Graphene Composite Materials Synthesized Using a Microwave-Assisted Catalytic Graphitization Process.

Faridul Islam,Jianglong Yu,Arash Tahmasebi,Rou Wang

doi:10.3390/nano11071672

Abstract

Metal-supported few-layer graphene (FLG) was synthesized via microwave-assisted catalytic graphitization owing to the increasing demand for it and its wide applications. In this study, we quickly converted earth-abundant and low-cost bituminous coal to FLG over Fe catalysts at a temperature of 1300 °C. X-ray diffraction, Raman spectroscopy, transmission electron microscopy, and N2 adsorption–desorption experiments were performed to analyze the fabricated metal-supported FLG. The results indicated that the microwave-irradiation temperature at a set holding-time played a critical role in the synthesis of metal-supported FLG. The highest degree of graphitization and a well-developed pore structure were fabricated at 1300 °C using a S10% Fe catalyst for 20 min. High-resolution transmission electron microscopy analysis confirmed that the metal-supported FLG fabricated via microwave-assisted catalytic graphitization consisted of 3–6 layers of graphene nanosheets. In addition, the 2D band at 2700 cm−1 in the Raman spectrum of the fabricated metal-supported FLG samples were observed, which indicated the presence of few-layer graphene structure. Furthermore, a mechanism was proposed for the microwave-assisted catalytic graphitization of bituminous coal. Here, we developed a cost-effective and environmental friendly metal-supported FLG method using a coal-based carbonaceous material.

Highlights

Accepted: 16 June 2021Graphene consists of single layers of sp2 –hybridized C atoms organized in a twodimensional honeycomb matrix
The 2D band at 2700 cm−1 in the Raman spectrum of the fabricated metalsupported FLG samples were observed, which indicated the presence of few-layer graphene structure
In this study we developed a cost-effective, time-efficient catalytic method for the synthesis of metal-supported FLG from bituminous coal using a microwave temperature of 1300 ◦ C

Summary

Introduction

Accepted: 16 June 2021Graphene consists of single layers of sp2 –hybridized C atoms organized in a twodimensional honeycomb matrix. Numerous graphene synthesis methods using gaseous hydrocarbons as C sources have been developed, such as chemical vapor deposition (CVD) [2], chemical or electrochemical processes [3], epitaxial growth [4], and graphite-oxide exfoliation [5]. Utilization of coal as a fossil fuel has been linked to climate change [8], air pollution, and human health problems [9]; fossil fuel depletion is a global-scale phenomenon that impacts the environment [10]. These shortcomings have led to the development of an alternative efficient and clean graphene synthesis method [11]. Graphite is used as a raw material for graphene oxide

Methods

Results

Conclusion