During the oil and gas exploitation, the corrosion of carbon steel pipes causes great economic loss, heavy casualties, environmental pollution, and waste of resources. The development of highly efficient and stable corrosion inhibitors is of great significance for the corrosion protection of carbon steel in oil and gas exploitation. L-cysteine is widespread in various plants (e.g. onion, cauliflower, and cabbage sprout). As a corrosion inhibitor, it usually has low inhibitive efficiency in most corrosive environment. Chemical modification is the most efficient method to solve this issue. Herein, two synthetic amino acid derivatives (2-phenylthiazolidine-4-carboxylic acid (PTCA) and 2-(thiophen-2-yl)thiazolidine-4-carboxylic acid (TTCA)) were investigated as high-efficient corrosion inhibitors to deal with the corrosion issue of carbon steel in the CO₂-containing environment. The anti-corrosion property of the amino acid derivatives was investigated by electrochemical experiment, surface technique and theoretical calculations. The electrochemical results show that PTCA and TTCA present high corrosion inhibition efficiencies at the concentration of 0.8 mM: PTCA (99.1%) and TTCA (99.3%). The inhibitive mechanism of PTCA and TTCA on carbon steel surface is revealed by theoretical calculations. It is found that the PTCA and TTCA adsorb at the steel/solution interface by forming Fe-O bonds. Compared to PTCA, TTCA exhibits stronger adsorption on carbon steel surface by forming shorter Fe-O bonds with a more negative adsorption energy, which accounts for the better inhibitive performance of TTCA.

在油气开采过程中，碳钢管的腐蚀造成了巨大的经济损失、人员伤亡、环境污染和资源浪费。开发高效稳定的缓蚀剂对油气开采中碳钢的腐蚀防护具有重要意义。大号-半胱氨酸广泛存在于各种植物中（例如洋葱、花椰菜和卷心菜芽）。作为缓蚀剂，通常在大多数腐蚀环境中缓蚀效率较低。化学修饰是解决这个问题最有效的方法。在此，研究了两种合成氨基酸衍生物（2-苯基噻唑烷-4-羧酸（PTCA）和 2-（噻吩-2-基）噻唑烷-4-羧酸（TTCA））作为高效腐蚀抑制剂来处理碳钢在CO _{2中的腐蚀问题}-包含环境。通过电化学实验、表面技术和理论计算研究了氨基酸衍生物的防腐性能。电化学结果表明，PTCA 和 TTCA 在浓度为 0.8 mM 时表现出高腐蚀抑制效率：PTCA (99.1%) 和 TTCA (99.3%)。通过理论计算揭示了PTCA和TTCA对碳钢表面的抑制机理。发现 PTCA 和 TTCA 通过形成 Fe-O 键吸附在钢/溶液界面。与 PTCA 相比，TTCA 通过形成更短的 Fe-O 键和更负的吸附能在碳钢表面表现出更强的吸附，这是 TTCA 更好的抑制性能的原因。