Synthesis, Characterization and Investigation of Anticorrosion Properties of an Innovative Metal–Organic Framework, ZnMOF-BTA, on Carbon Steel in HCl Solution

An innovative metal–organic framework (ZnMOF-BTA) with corrosion inhibition properties was prepared by the solvothermal reaction of zinc nitrate, 1,2,3-benzotriazole, and 2,5-thiophene dicarboxylic acid. ZnMOF-BTA was characterized by FTIR, XRD, XPS, SEM, and thermogravimetric analyses, and the corrosion inhibition performance on Q235 carbon steel in 1 M HCl solution was evaluated by weight loss, polarization, and EIS measurements. XRD results showed that ZnMOF-BTA has a monoclinic crystal structure and belongs to C12/c1 space group, while DTA/TGA results revealed it has a good crystalline quality and excellent thermal stability with a melting point of 410 °C. FTIR and XPS results revealed that Zn2+, TDC2−, and BTA molecules were successfully used in ZnMOF-BTA synthesis. Electrochemical test results show that the obtained ZnMOF-BTA is effective in corrosion inhibition of Q235 carbon steel in acidic conditions and maximum inhibition efficiency of over 90% is obtained at 6 wt.% ZnMOF-BTA extract concentration. Adsorption studies revealed that the adsorption of BTA molecules follows the Langmuir isotherm model with an R2 value of 0.97889, while the ΔG◦ads value of −10.28 kJ mol−1 indicates that adsorption is by physisorption. The study provides a new corrosion inhibitor compound with proven corrosion inhibition properties.