Borode Adeola O, Ahmed Noor A, Olubambi Peter A
Department of Mechanical Engineering Science, University of Johannesburg, Johannesburg, South Africa.
Department of Metallurgy, University of Johannesburg, Johannesburg, South Africa.
Heliyon. 2021 Jan 12;7(1):e05949. doi: 10.1016/j.heliyon.2021.e05949. eCollection 2021 Jan.
This study investigates the effect of different surfactant-dispersed graphene nanofluid on the electrochemical behavior of copper. This study was achieved by measuring the open circuit potential and potentiodynamic polarization of copper in the nanofluids at room temperature. The test media includes surfactant-free graphene nanofluid and graphene nanofluid dispersed using four different surfactants, which are sodium dodecyl sulfate, sodium dodecylbenzene sulfonate, Gum Arabic, and Tween 80. The surface characterization and elemental composition of the copper sample before and after the corrosion tests were determined using a scanning electron microscope coupled with energy-dispersive X-ray spectroscopy. The phase formation after corrosion was also evaluated by measuring X-ray diffraction. The quantity of copper dissolved in the test media was evaluated using an inductively coupled plasma mass spectrometry (ICP-MS). The open-circuit potential measurements revealed that the current free corrosion potential of copper in the different surfactant-aided graphene nanofluids are different. The electrochemical corrosion potential, Tafel slopes, and corrosion rates revealed the better corrosion performance of copper in the nanofluid of different surfactants in the increasing order GA, SDS, Tween 80, and SDBS. Copper in GA-based graphene nanofluid was found to have the lowest corrosion rate while that of SDBS has the highest corrosion rate. However, the ICP-MS result revealed a discrepancy in the corrosion behavior and quantity of copper dissolved in the different test media. This could be attributed to the dissimilar dissolution-redeposition rate of copper in different media.
本研究考察了不同表面活性剂分散的石墨烯纳米流体对铜的电化学行为的影响。该研究通过在室温下测量铜在纳米流体中的开路电位和动电位极化来实现。测试介质包括无表面活性剂的石墨烯纳米流体以及使用四种不同表面活性剂分散的石墨烯纳米流体，这四种表面活性剂分别是十二烷基硫酸钠、十二烷基苯磺酸钠、阿拉伯胶和吐温80。使用扫描电子显微镜结合能量色散X射线光谱法测定了腐蚀试验前后铜样品的表面特征和元素组成。还通过测量X射线衍射评估了腐蚀后的相形成情况。使用电感耦合等离子体质谱法（ICP-MS）评估了溶解在测试介质中的铜的量。开路电位测量结果表明，铜在不同表面活性剂辅助的石墨烯纳米流体中的自腐蚀电位不同。电化学腐蚀电位、塔菲尔斜率和腐蚀速率表明，铜在不同表面活性剂的纳米流体中的腐蚀性能由低到高依次为阿拉伯胶、十二烷基硫酸钠、吐温80和十二烷基苯磺酸钠。发现基于阿拉伯胶的石墨烯纳米流体中的铜腐蚀速率最低，而十二烷基苯磺酸钠中的铜腐蚀速率最高。然而，ICP-MS结果显示不同测试介质中铜的腐蚀行为和溶解量存在差异。这可能归因于铜在不同介质中不同的溶解-再沉积速率。
