Abstract
In the present work, we characterize the physical, morphological, and chemical structures of natural melanin doped with various transition metals (Fe, Cu, and Zn ions) by utilizing different techniques, such as transmission electron spectroscopy (TEM), Scanning Electron Microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and Fourier transform infrared spectroscopy (FTIR). The thermogravimetric analysis (TGA) revealed that melanin can bond strongly with metal ions (Fe, Cu, and Zn). The electrical conductivity of melanin interacting with Cu, Fe, and Zn metals was found to increase with the addition of metal ions. It is anticipated that the inorganic–organic composites could exhibit valuable electrical and photothermal properties, which may change the functionality of biopolymer devices.
•We characterized the physical, and chemical structures of melanin doped with Fe, Cu, and Zn ions.•The TGA was employed to analyze the thermal stability of melanin-metals.•It was revealed that melanin can bond strongly with metal ions (Fe, Cu, and Zn).•The electrical conductivity varies with the change of the doping of Cu, Fe, and Zn ions in melanin.•The systems exhibited valuable physical properties that may change the biopolymer functionalities