Electrophoretic deposition (EPD) of surface modified graphene oxide (GO) on copper substrate for anti-corrosion applications

다국어 초록 (Multilingual Abstract)

Anti-corrosion of metals is a vital issue for many industries requiring novel methods that could delay the corrosion processes. The most recent studies suggest the use of graphene for the control of corrosion due to its uniquely impermeable 2D structure which simultaneously exhibits an exceptional barrier to reactive liquids, salts and acids. Here, p-phenylenediamine modified graphene oxide (PPD-GO) coating for anti-corrosion performance is fabricated on copper by an electrophoretic deposition (EPD) method using the colloids of PPD-GO in ethanol. In order to establish the influence of the EPD parameters on the properties of the deposited films, the EPD kinetics of PPD-GO is investigated as a function of concentration, deposition time and voltage, accompanied by microscopic characterization of the deposited films. The experimental results show that the deposition follows a linear growth law, in good agreement with the predictions of Hamaker’s law. The uniform PPD-GO coating allows the tightly-consolidation, excellent adhesion and highly anti-corrosion performance, which are further developed during thermal treatment. According to the results of the potentiodynamic polarization method, the decrease in corrosion current density and the positive shift in corrosion potential have both demonstrated that PPD-GO coating served as a corrosion inhibitor, protecting copper from NaCl aqueous solution.

목차 (Table of Contents)

• Abstract 6
• 1. Introduction 8
• 2. Background 13
• 2.1. Graphene. 13
• 2.1.1. Properties & applications of graphene 13
• 2.1.2. Barrier properties of graphene. 13
• 2.2. Electrophoretic deposition (EPD) method. 16
• 2.2.1. Introduction of EPD 16
• 2.2.2. EPD kinetics. 19
• 2.2.3. Factors affecting EPD 19
• 2.2.4. Graphene suspensions for EPD 24
• 2.3 Corrosion. 25
• 2.3.1. Basics of corrosion 25
• 2.3.2. Polarization. 26
• 2.3.3. Passivity.. 31
• 2.4 Corrosion test 32
• 2.4.1. Electrochemical Methods for the Study of Corrosion 32
• 2.4.2. Electrochemical Polarization Technique. 33
• 2.4.3. Tafel polarization methods 35
• 3. Experimental. 37
• 3.1. Materials. 37
• 3.2. Procedure for p-phenylenediamine modified graphene oxide (PPD-GO) solution 37
• 3.3. Preparation of PPD-GO coated copper & EPD experiment 37
• 3.4. Characterization 38
• 3.5. Kinetics for EPD of PPD-GO 39
• 3.6. Electrochemical corrosion test 39
• 4. Results and discussion. 41
• 4.1. PPD-GO suspensions for EPD 41
• 4.2. Kinetics of electrophoretic deposition 45
• 4.3. Thermal stability. 51
• 4.4. Composition analysis 52
• 4.5. Cross-cut adhesion test. 54
• 4.6. Anti-corrosion performance 56
• 5. Conclusions 61
• References 62