Study on Preparation and Properties of the Graphene Functional Layer by the Spray Coating Method

Abstract

Stable aqueous graphene dispersion with sodium dodecyl benzene sulfonate (SDBS) surfactant was prepared by using an ultrasonic dispersing process. Graphene films were deposited on glass and silicon substrate as functional layers by the spray coating method. The study of the influence of SDBS concentration on graphene dispersing performance show that SDBS concentration of 15% is adequate for preparing stable graphene dispersion. Optical and morphological properties of the resulting graphene films are also investigated by ultraviolet-visible spectrophotometer and scanning electron microscopy, respectively. The results indicate that the visible light transmittance of graphene coating is higher than 82% and the graphene film shows a cluster structure with blade-like edges. The field emission analyses were carried out by a diode test cell in a vacuum system, which confirms that this graphene functional layer has good field-emission performance with low turn-on field of 3 V/μm and large enhancement factor of 3 580. Collectively, this deposition method may be a viable and cost-effective route for fabricating graphene films.