Abstract A series of pyrazole ligands named as 1,4-bis(3,5-dimethylpyrazol-1-yl)butane (bbd), 1,3-bis(3,5-dimethylpyrazol-1-yl)propane (bdpp), and 1,3-bis(3,5-dimethylpyrazol-1-yl)propane-2-ol (bdpo) along with their transition metal complexes including [Cu2(µ3-SCN)2(µ-bbd)]n, [Cu2(µ3-SCN)2(µ-bdpp)]n, and [Cu2Hg(µ2-SCN)2(bdpo)2(CH3COO)2]n were synthesized and characterized using FT-IR and Uv-vis spectroscopies, as well as thermal gravimetric analysis. The prepared compounds were investigated as corrosion inhibitors to protect mild steel in 0.5 M H2SO4 solution. Corrosion tests were performed by electrochemical impedance spectroscopy and potentiodynamic polarization measurements. The pyrazole ligands exhibited inhibition efficiencies in a range of 38–78%, which introduced them as moderate inhibitors. On the other hand, the pyrazole complexes showed inhibition efficiencies higher than 85%, demonstrating their high potentials to mitigate the steel corrosion. In addition, the bimetallic complex resulted in higher corrosion resistance than the two monometallic complexes. This was evidence of a critical role of the coordinated metal of the complex in forming an adhesive protection film on the steel surface.

中文翻译：

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吡唑配体及其单金属和双金属配合物：合成、表征和作为新型缓蚀剂的应用

摘要 一系列吡唑配体命名为 1,4-双(3,5-二甲基吡唑-1-基)丁烷 (bbd), 1,3-双(3,5-二甲基吡唑-1-基)丙烷 (bdpp),和 1,3-双(3,5-二甲基吡唑-1-基)丙烷-2-醇 (bdpo) 及其过渡金属配合物，包括 [Cu2(µ3-SCN)2(µ-bbd)]n、[Cu2 (μ3-SCN)2(μ-bdpp)]n 和 [Cu2Hg(μ2-SCN)2(bdpo)2(CH3COO)2]n 合成并使用 FT-IR 和紫外可见光谱进行表征，以及热重分析。研究制备的化合物作为腐蚀抑制剂以保护 0.5 M H2SO4 溶液中的低碳钢。通过电化学阻抗谱和动电位极化测量进行腐蚀测试。吡唑配体表现出 38-78% 的抑制效率，这将它们作为中度抑制剂引入。另一方面，吡唑配合物显示出高于 85% 的抑制效率，表明它们在减轻钢腐蚀方面具有很高的潜力。此外，双金属配合物比两种单金属配合物具有更高的耐腐蚀性。这证明了配合物的配位金属在钢表面形成粘合保护膜中的关键作用。