Properties of Layered PbI2 Doped with Al and Co
Ali M. Mousa , Natheer J. Al-rubaie

Investigation of Co and Al doping in lead iodide using X-ray diffraction, electrical measurements and optical transmission was carried out. Doping introduces donor's levels, whose ionization energies were determined. Different doping levels changes band gap, also doping induces an energy level shift with the two dopants. Study of the doping efficiency as a function of the growth conditions indicates that the compensation mechanism is related to the incorporation of dopants in the deposited layer. With the dopants weights increasing, a sharp drop in resistivity of over (47) orders of magnitude was observed at 3 mg Co. A comparative study of various doped PbI2 indicates that presence of Co and Al atoms strongly enhances the layers photoconductivities. It appears that the photoconductivity ratios of doped PbI2 layers are size-insensitive.
Key words: Lead iodide, dark conductivity, photoconductivity, solution deposition.