Synthesis, Characterization, and Evaluation of Co-MOF Based ZIF-67 for CO2 Corrosion Inhibition of X65 Steel: Insights from Electrochemical Studies and a Machine Learning Algorithm

Co-MOFbased metal organic framework was synthesized by reactinga metal ion (cobalt nitrate hexahydrate) with an organic ligand (2-methylimidazole)via a wet chemical method. The resulting material was characterizedusing detailed analytical methods and further was used as a self-assemblycorrosion inhibitor in sweet corrosive environment. The empiricaldata set via electrochemical studies was modeled using adaptive neurofuzzy inference system (ANFIS). The observed results showed that Co-MOFcould significantly impede the corrosion rate of X65 steel and protectit from CO2 corrosion. Increasing the concentration ofCo-MOF in the test solution increased the inhibition efficiency upto 97% at 0.1 wt % Co-MOF with a mixed-type inhibition mechanism.In addition, the DFT/MD-simulation approach evidenced the adsorptiondisposition of Co-MOF in aqueous and gas phase which complement withthe empirical findings. Also, the prognostic capability of the proposedalgorithm based on the statistical parameters such as root-mean-squareerror (RMSE), chi square (chi(2)), model predictive error(MPE) and coefficient of determination (R-2) were appraised.From the viewpoint of statistics, the explanatory model aligned crediblywith the ANFIS algorithm. The overall findings confirmed a dense hybridcoating of the synthesized Co-MOF on X65 steel as responsible forthe inhibition of the sweet corrosion.