Chemometrics applied quantitative analysis of iron oxide mixtures by terahertz spectroscopy

A quantitative analysis method for corrosion products based on terahertz spectroscopy is proposed in this paper. Mixture samples consisting of three major corrosion products (magnetite, hematite, and goethite) were prepared in 51 different concentrations. The refractive index spectra measured by terahertz time-domain spectroscopy were projected to the 2D score diagram by performing principal component analysis. The Euclidean distances between the mixtures and pure analyte on the diagram were used to build a concentration prediction model. The results indi-cate that the established model can precisely predict the concentration of magnetite, which is essential for a stability evaluation of the corrosion system.(c) 2023 Optica Publishing Group

Automated summary

This paper proposes a quantitative analysis method for corrosion products based on terahertz spectroscopy. Mixture samples of three major corrosion products (magnetite, hematite, and goethite) at 51 different concentrations were prepared. The refractive index spectra measured by terahertz time-domain spectroscopy were projected to a 2D score diagram using principal component analysis. The established model based on the Euclidean distances between mixtures and pure analyte on the diagram can accurately predict the concentration of magnetite, which is crucial for assessing the stability of the corrosion system.