Tamilselvi Baluchamy, Bhuvaneshwari Durvas Seshian, Karuppasamy Periyakaruppan, Padmavathy Sethuramasamy, Nikhil Santhosh, Siddegowda Surendra Boppanahalli, Ananda Murthy H C
Department of Chemistry, Thiagarajar College, Madurai 625009, Tamil Nadu, India.
Department of Chemistry, K.L.N. College of Engineering, Pottapalaiyam 630612, Tamil Nadu, India.
ACS Phys Chem Au. 2023 Dec 8;4(1):67-84. doi: 10.1021/acsphyschemau.3c00055. eCollection 2024 Jan 24.
Corrosion inhibition of mild steel (MS) was studied using isolate in 0.5 M HSO, which was isolated from rotten grapes () via biofilm formation. Biofilm over the MS surface was asserted by employing FT-IR and FE-SEM with EDXS, electrochemical impedance spectroscopy (EIS), AFM, and DFT-ESP techniques. The weight loss experiments and temperature studies supported the physical adsorption behavior of the corrosion inhibitors. The maximum inhibition efficiency (IE) value (90%) was observed at 293 K for 9 × 10 cfu/mL of isolate. The adsorption of isolate on the surface of MS confirms Langmuir's adsorption isotherm model, and the -Δ values indicate the spontaneous adsorption of inhibitor over the MS surface. Electrochemical studies, such as potentiodynamic polarization (PDP) and EIS were carried out to investigate the charge transfer (CT) reaction of the isolate. Tafel polarization curves reveal that the isolate acts as a mixed type of inhibitor. The Nyquist plots (EIS) indicate the increase in charge transfer resistance () and decrease of double-layer capacitance () values when increasing the concentration of isolate. The spectral studies, such as UV-vis and FT-IR, confirm the formation of a complex between MS and the isolate inhibitor. The formation of biofilm on the MS surface was confirmed by FE-SEM, EDXS, and XPS analysis. The proposed bioinhibitor shows great potential for the corrosion inhibition of mild steel in acid media.
使用从腐烂葡萄中通过生物膜形成分离得到的菌株，在0.5 M硫酸中研究了低碳钢（MS）的缓蚀性能。通过傅里叶变换红外光谱（FT-IR）、配备能谱仪（EDXS）的场发射扫描电子显微镜（FE-SEM）、电化学阻抗谱（EIS）、原子力显微镜（AFM）和密度泛函理论-静电势（DFT-ESP）技术确定了低碳钢表面的生物膜。失重实验和温度研究支持了缓蚀剂的物理吸附行为。对于9×10 cfu/mL的菌株，在293 K时观察到最大缓蚀效率（IE）值为90%。菌株在低碳钢表面的吸附符合朗缪尔吸附等温线模型，负的吉布斯自由能变（-ΔG）值表明缓蚀剂在低碳钢表面的自发吸附。进行了动电位极化（PDP）和EIS等电化学研究，以研究菌株的电荷转移（CT）反应。塔菲尔极化曲线表明，该菌株为混合型缓蚀剂。奈奎斯特图（EIS）表明，随着菌株浓度的增加，电荷转移电阻（Rct）增大，双层电容（Cdl）值减小。紫外可见光谱（UV-vis）和傅里叶变换红外光谱（FT-IR）等光谱研究证实了低碳钢与菌株缓蚀剂之间形成了络合物。通过FE-SEM、EDXS和X射线光电子能谱（XPS）分析证实了低碳钢表面生物膜的形成。所提出的生物缓蚀剂在酸性介质中对低碳钢的缓蚀具有很大潜力。
