In this study, we evaluate the efficiency of Garcinia fruit rind extract (GIW) as a green inhibitor for mild steel in HCl medium. The aqueous extract is rich in cyanidin and anthocyanin pigments and their presence are detected by a peak around 520 nm in the UV–Visible spectrum and the functional groups with oxygen atoms and aromatic rings are found from the IR spectrum. The inhibition efficiency is determined by weight loss and electrochemical methods. GIW act as an effective inhibitor giving 93% efficiency in 0.5 M HCl and 87% for 1 M HCl at 303 K and 80% for 1 M HCl at 333 K. GIW act as a mixed type inhibitor and the inhibition mechanism is by monolayer adsorption of constituent molecules of GIW, which obeys Langmuir adsorption isotherm. The quantum chemical calculations on chief constituent molecules of GIW show that they can be adsorbed on the metal surface through free OH groups or π electrons. The cyanidin molecules exist as oxonium ion in HCl and engage in back bonding with metal-cantered orbitals.

在这项研究中，我们评估了藤黄果皮提取物（GIW）作为HCl介质中低碳钢绿色抑制剂的效率。水性提取物富含花青素和花青素色素，可通过紫外可见光谱中520 nm附近的峰检测到它们的存在，并从红外光谱中发现带有氧原子和芳环的官能团。抑制效率由重量损失和电化学方法确定。GIW充当有效的抑制剂，在303 K时在0.5 M HCl中的效率为93％，在1 M HCl中为87％，在333 K时的1M HCl为80％。GIW充当混合型抑制剂，其抑制机理是通过单层吸附服从Langmuir吸附等温线的GIW组成分子。GIW的主要组成分子的量子化学计算表明，它们可以通过自由的OH基团或π电子吸附在金属表面上。花青素分子在HCl中以氧离子的形式存在，并与金属掺杂的轨道反向键合。