Graphene Synthesis by Ultrasound Energy-Assisted Exfoliation of Graphite in Various Solvents

• Published in: Crystals (Basel) Vol. 10; no. 11; p. 1037
• Main Authors: Gürünlü, Betül, Taşdelen-Yücedağ, Çiğdem, Bayramoğlu, Mahmut
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01-11-2020
• Subjects: Acoustics; Atomic force microscopy; Cavitation; Chemical vapor deposition; Crystal structure; Dimethyl sulfoxide; Dimethylformamide; Energy; Exfoliation; Graphene; graphene synthesis; Graphite; Ionic liquids; Liquid phases; liquid-phase exfoliation; Mechanical properties; Methods; Micrometers; Morphology; Multilayers; Particle size; Perchloric acid; Photon correlation spectroscopy; Polydispersity; Solvents; Spectrum analysis; Surfactants; Titanium alloys; Transmission electron microscopy; Ultrasonic imaging; Ultrasound; X-ray diffraction; Zeta potential; United States > US
• ISSN: 2073-4352; 2073-4352
• DOI: 10.3390/cryst10111037

The liquid-phase exfoliation (LPE) method has been gaining increasing interest by academic and industrial researchers due to its simplicity, low cost, and scalability. High-intensity ultrasound energy was exploited to transform graphite to graphene in the solvents of dimethyl sulfoxide (DMSO), N,N-dimethyl formamide (DMF), and perchloric acid (PA) without adding any surfactants or ionic liquids. The crystal structure, number of layers, particle size, and morphology of the synthesized graphene samples were characterized by X-ray diffraction (XRD), atomic force microscopy (AFM), ultraviolet visible (UV–vis) spectroscopy, dynamic light scattering (DLS), and transmission electron microscopy (TEM). XRD and AFM analyses indicated that G-DMSO and G-DMF have few layers while G-PA has multilayers. The layer numbers of G-DMSO, G-DMF, and G-PA were determined as 9, 10, and 21, respectively. By DLS analysis, the particle sizes, polydispersity index (PDI), and zeta potential of graphene samples were estimated in a few micrometers. TEM analyses showed that G-DMSO and G-DMF possess sheet-like fewer layers and also, G-PA has wrinkled and unordered multilayers.