喷涂法制备石墨烯功能层及性能研究

以十二烷基苯磺酸钠（SDBS）为表面活性剂，采用超声分散工艺制备出稳定的石墨烯水分散液，并采用喷涂法分别在玻璃和n-Si基底上形成石墨烯薄膜。研究了表面活性剂浓度对石墨烯分散效果的影响。结果表明，采用浓度为15%的SDBS可获得稳定的石墨烯水溶液分散液。利用分光光度计和扫描电镜对石墨烯薄膜的透过率和表面形貌进行表征，结果表明其可见光透过率超过82%，薄膜具有刀刃状的边缘结构。采用二极管结构对石墨烯薄膜的场发射性能进行测试，其开启电场为3V/μm，场增强因子为3 580。实验结果表明，这是一种可行的、低成本的制作石墨烯功能层的有效方法。

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

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.