Optoelectronic and electrochemical behaviour of γ-CuI thin films prepared by solid iodination process

A simple and efficient solid iodination method has been proposed for the fabrication of p-type gamma-CuI thin films. The structural, morphological, optical, electrical and electrochemical properties have been investigated in order to serve as an effective hole-transporting layer in solid-state solar cells. The fabricated films exhibited p-type conductivity with resistivity of 7.0 x 10(-2) Omega cm, the hole concentration of similar to 1.13 x 10(19) Cm-3 and the mobility of 18.34 cm(-2) V-1 s(-1). The cyclic voltammetry result shows a maximum specific capacitance of 43 mF/cm(2) at a scan rate of 10 mV/s. The cyclic stability and capacitance retention were found to be 99.7%. These findings demonstrate that gamma-CuI film can be a potential candidate for multiple applications, such as a hole transporting material for solid-state solar cells and electrochemical supercapacitor.