Abstract—Graphene has gained much attention owing to its unique optical and electrical properties. Charge carriers in graphene sheets (GS) carry out a linear dispersion relation near the Fermi energy and behave as massless Dirac fermions resulting in unusual attributes such as the quantum Hall effect and ambipolar electric field effect. It also exhibits nondispersive transport characteristics with an extremely high electron mobility (15000 cm 2 /(Vs)) at room temperature. Recently, several progresses have been achieved in the fabrication of single- or multilayer GS for functional device applications in the fields of optoelectronic such as field-effect transistors ultrasensitive sensors and organic photovoltaic cells. In addition to device applications, graphene also can serve as reinforcement to enhance mechanical, thermal, or electrical properties of composite materials. Electrophoretic deposition (EPD) is an attractive method for development of various coatings and films. It readily applied to any powdered solid that forms a stable suspension. The deposition parameters were controlled in various thicknesses. In this study, the graphene electrodeposition conditions were optimized. The results were obtained from SEM, Ohm resistance measuring technique and AFM characteristic tests. The minimum sheet resistance of electrodeposited reduced graphene oxide layers is achieved at conditions of 2 V in 10 s and it is annealed at 200 °C for 1 minute. Keywords—Electrophoretic deposition, graphene oxide, electrical conductivity, electro-optical devices. I. INTRODUCTION RAPHENE with unique electrical, optical and mechanical properties has been used for many aspects of opto-electronic devices [1], [2]. Depending on the chemical structure and properties of graphene, it is produced in different methods [3], [4]. Graphene has many advantages due to quantum effects of a single atomic layer or few atomic layers [5]. Graphene oxide (GO) can be reduced via using different methods [5], [6]. Due to the difference in the conductivity between reduced GO and GO, an easy and efficient way to deploy reduced GO is required in many applications [7]-[9]. EPD method is used for applying graphene and graphene- Sepehr Lajevardi Esfahani is with the Department of Organic Colorants, Institute for Color Science and Technology, Tehran, Iran (corresponding author, phone: +989126724627, e-mail: lajevardi_sepehr20@yahoo.com). Shohre Rouhani is with the Department of Organic Colorants, Institute for Color Science and Technology, Center of excellence for Color Science and Technology(CECST), Institute for Color Science and Technology, Tehran, Iran (e-mail: rouhani@icrc.ac.ir). Zahra Ranjbar is with the Department of Organic Coatings and novel technologies, Institute for Color Science and Technology, Center of excellence for Color Science and Technology(CECST), Institute for Color Science and Technology, Tehran, Iran (e-mail: ranjbar@icrc.ac.ir). based nanomaterials for a wide range of applications, including materials for energy storage [10], fuel cells, solar cells [11], super capacitors and sensors [12]. This type of carbon nanomaterial can be dispersed in organic solvents mainly in water [13], [14]. Most materials are electrophoretically applied under constant electrical potential in different application times [15]. These two parameters (electrical potential and time of application) play an important role in the morphology of created nanomaterial layers [16]. In addition to the simple planar substrates, researches have shown that graphene can interact on the basis of uniform layers on complex three-dimensional substrates, porous, and flexible substrates through EPD method [17]-[19]. In general, the graphene layers applied by EPD show that excellent properties, for example, high electrical conductivity, large surface area, good thermal stability, high optical transparency and appropriate mechanical strength [20]-[23]. Also, the composites contain graphene are applicable very well by EPD, e.g. graphene with metallic nanoparticles or carbon combined with other materials like carbon nanotubes (CNT) [24], [25]. Given the importance of using a highly conductive substrate with a facile manufacturing process in opto-electronic devices, graphene as an appropriate material is known in this field [26]-[29]. In various investigations, formation of graphene layers by EPD method is introduced, but optimization of all parameters involved in the process of electrophoretic depositing of graphene to ensure all electrical and optical properties suitable for opto-electronic applications is not fully performed yet. In this study, we have tried to meet this challenge. Although several studies have investigated the EPD of GO, the key parameter’s effect of EPD process on thickness and conductivity of uniform film has not been investigated completely. In this research work, anodic electrodeposition of stable GO suspension was done on bare copper foil. The key parameters of EPD process (concentration of GO suspension, electrical potential and application time) due to the better morphology and electrical conductivity and minimum thickness of electrodeposited GO layers were optimized. II. EXPERIMENTAL A. Materials The used materials (with their suppliers) are included of GO nano-platelets (Nanosany Co.), Mg(NO 3 ) 2 , NaOH, Methoxy Optimization the Conditions of Electrophoretic Deposition Fabrication of Graphene-Based Electrode to Consider Applications in Electro-Optical Sensors Sepehr Lajevardi Esfahani, Shohre Rouhani, Zahra Ranjbar G World Academy of Science, Engineering and Technology International Journal of Chemical and Molecular Engineering Vol:11, No:12, 2017 781 International Scholarly and Scientific Research & Innovation 11(12) 2017 scholar.waset.org/1307-6892/10008339 International Science Index, Chemical and Molecular Engineering Vol:11, No:12, 2017 waset.org/Publication/10008339