Investigating the Properties of Graphite Oxide Suspension, Films, and Papers Produced from Natural Graphite of Southern Yakutia

Abstract

An aqueous suspension of graphite oxide (GrO) was prepared from natural Yakut graphite by modified Hummers′ method. The lateral size of GrO flakes varied from 0.1 μm to 10 μm, their thickness was 20 nm. The fabricated suspension, GrO films (of various thickness and on various substrates), and GrO papers were studied in terms of their structural, optical, and electrophysical characteristics. The obtained GrO films are dielectrics with quite large resistance varying from 12.5.10⁶–4.6.10⁹ Ω depending on their thickness. The films are characterized by the luminescence in the region of 380–650 nm, the presence of oxygen-containing groups–ОН,–СООН,–С=О,–СОН, СОО–, and the transparency of 91% for a 20 nm thick film at the wavelength of 670 nm. The conducted study testifies high quality of Yakut graphite, which can be quite easily exfoliated. GrO films possess high resistance and transparency.