Hoai Vu Nguyen Si, Hien Pham Van, Mathesh Motilal, Hanh Thu Vu Thi, Nam Nguyen Dang
Faculty of Physics and Engineering Physics, University of Science, VNU-HCM, 227 Nguyen Van Cu Street, District 5, Ho Chi Minh City 700000, Vietnam.
Institute of Fundamental and Applied Sciences, Duy Tan University, 10C Tran Nhat Duat Street, District 1, Ho Chi Minh City 700000, Vietnam.
ACS Omega. 2019 Jan 3;4(1):146-158. doi: 10.1021/acsomega.8b02084. eCollection 2019 Jan 31.
A porous and low-density protective film on a steel surface in the corrosive environment can undergo deterioration even in the presence of organic inhibitors due to infiltration of aggressive ions into the pinholes and/or pores. This phenomenon is related to the localized corrosion that takes place even in the presence of an optimal concentration of organic corrosion inhibitors in the given medium. To overcome this issue, we have designed an organic protective film on a steel surface with the help of titania nanoparticles (TNPs) combined with an organic corrosion inhibitor derived from leaf extract (APLE), all to be studied in a simulated ethanol fuel blend (SEFB). The TNPs with varied diameters and concentrations have been studied for examining their effect on the inhibition capacity of 1000 ppm APLE on the steel surface in SEFB medium using electrochemical and surface analysis techniques. Enhanced corrosion inhibition of the surficial film was observed in the presence of both the APLE inhibitor and small amounts of TNPs. A direct agreement was observed between the experimental and molecular dynamics theoretical investigations showcasing high binding energy between inhibitor molecules and steel substrates, resulting in a much higher adhesion of the protective film, good thermal stability of the adsorbent film, and electron abundance for the supply of steel substrate of inhibitor species.
在腐蚀环境中，钢表面的多孔低密度保护膜即使在有有机缓蚀剂存在的情况下，也可能因侵蚀性离子渗入针孔和/或孔隙而发生劣化。这种现象与局部腐蚀有关，即使在给定介质中存在最佳浓度的有机腐蚀缓蚀剂时也会发生局部腐蚀。为了克服这个问题，我们借助二氧化钛纳米颗粒（TNPs）与源自树叶提取物的有机腐蚀缓蚀剂（APLE），在钢表面设计了一种有机保护膜，所有这些都将在模拟乙醇燃料混合物（SEFB）中进行研究。使用电化学和表面分析技术，研究了不同直径和浓度的TNPs对1000 ppm APLE在SEFB介质中对钢表面的缓蚀能力的影响。在APLE缓蚀剂和少量TNPs同时存在的情况下，观察到表面膜的缓蚀作用增强。实验和分子动力学理论研究之间观察到直接的一致性，表明缓蚀剂分子与钢基底之间具有高结合能，从而导致保护膜的附着力更高、吸附膜具有良好的热稳定性以及缓蚀剂物种向钢基底供应的电子丰度。
