Simultaneous Bismuth and Copper Determination from Full Differential Pulse Voltammogram Using XGBoost and Gradient Boosting Regression

In this study, the differential pulse voltammetry (DPV) method was used to simultaneously determine bismuth and copper concentrations. A ۲۵ bismuth and copper mixtures at the designed ratio were measured using the DPV technique. However, the overlapping differential pulse voltammograms obtained made it difficult to quantitatively analyze the concentrations based on adaptive peak current selection. To address this issue, the voltammograms were preprocessed using derivatization and peak subtraction. The second derivative voltammogram was found to be highly correlated with the copper-bismuth concentration ratio, resulting in improved fit and prediction accuracy. To further improve the accuracy and precision of the training and prediction results, XGBoost and Gradient Boosting regression models were applied. The XGBoost and Gradient Boosting regression models showed high accuracy and precision with r-squared values of ۰.۸۷۷ and ۰.۹۹۳ for copper, and ۰.۸۷۹ and ۰.۹۹۳ for bismuth, respectively. The mean recoveries of copper were ۹۹.۸۴% and ۹۸.۰۷%, while bismuth recoveries were ۹۳.۱۷% and ۹۰.۸۵% for XGBoost and Gradient Boosting, respectively. Additionally, cross-validation using ۱۰ splits produced a mean score of ۴۵.۵۶۵ and a mean absolute error of ۱۳.۰۵۱ for copper, and a mean score of ۱۳.۶۰۰ and a mean absolute error of ۱۰.۹۲۰ for bismuth. Overall, the results indicate that the proposed method is an accurate and precise way to simultaneously determine bismuth and copper concentrations.

Keywords:

Bismuth , copper , Differential pulse voltammetry , XGBoost , Gradient Boosting , regression