Structure dependent optical and conductive properties of HPMC:CoCl2 composites: A functional data analysis study

This study rigorously investigates cobalt chloride doped hydroxypropyl methylcellulose composite films, taking a significant step toward understanding structure property relations. The aim is to develop biodegradable yet conductive polymer composites by meticulously examining the effects of incorporating a metal salt like cobalt chloride. The x-ray diffraction results obtained for these samples are analyzed to relate structure property dependencies. Conductivity tests provide valuable insights into variations in electrical conductivity, impedance, and dielectric properties. The optical bandgap obtained from UV/visible spectroscopic studies aligns with other studied physical parameters, supporting dopant-driven changes in these composites. In addition, employing the tightly bound electron model, we detail the bandgap variation in these composites concerning the dopant concentration. This study reveals that cobalt chloride is an effective dopant for modifying conductivity in a non-conductive polymer. Furthermore, we observe that the addition of CoCl2 in the polymer matrix forms packets of ordered regions, referred to as domains or crystalline grains. These domains act as sources of free ions and electrons, enhancing electrical and optical properties. Alongside experimental evidence, we employ a robust calculation method using functional data analysis to draw clear relationships among the parameters under study, further emphasizing the scientific rigor and significance of our findings.