Structural and Electrochemical Analysis of CIGS: Cr Crystalline Nanopowders and Thin Films Deposited onto ITO Substrates

Abstract

[EN] A new approach for the synthesis of nanopowders and thin films of CuInGaSe2(CIGS)chalcopyrite material doped with different amounts of Cr is presented. The chalcopyrite mate rial CuInxGa1 ¿ xSe2 was doped using Cr to form a new doped chalcopyrite with the structure CuInxCryGa1 ¿ x ¿ ySe2, where x = 0.4 and y = 0.0, 0.1, 0.2, or 0.3. The electrical properties of CuInxCryGa1 ¿ x ¿ ySe2 are highly dependent on the Cr content and results show these materials as promis ing dopants for the fabrication thin film solar cells. The CIGS nano-precursor powder was initially synthesized via an autoclave method, and then converted into thin films over transparent sub strates. Both crystalline precursor powders and thin films deposited onto ITO substrates following a spin-coating process were subsequently characterized using XRD, SEM, HR-TEM, UV¿visible and electrochemical impedance spectroscopy (EIS). EIS measurement was performed to evaluate the dc-conductivity of these novel materials as conductive films to be applied in solar cells.