Enhanced photoresponse of Cu(In,Ga)Se2/CdS heterojunction fabricated using economical non-vacuum methods

• DOI: 10.1007/s13391-014-4387-9
• Publication Date: 2015-06-29T22:32:14Z
• Authors: Sreekanth Mandati; Bulusu V. Sarada; Suhash R. Dey; Shrikant V. Joshi
• Keywords: Photocurrent

The present study demonstrates the fabrication of a CIGS/CdS heterojunction with enhanced photoelectrochemical performance using low-cost non-vacuum methods. A simplified economical pulse electrodeposition technique, with a two-electrode system in an additive-free electrolyte, has been used for the preparation of chalcopyrite Cu(In,Ga)Se2 (CIGS) thin-films avoiding the selenization process and CdS subsequently chemical bath deposited onto these CIGS films. Photoelectrochemical (PEC) performance of bare CIGS and the CIGS/CdS heterojunction has been investigated in conventional Na2SO4 electrolyte under chopped solar simulated light. The PEC analysis reveals nearly twenty-fold increase in the photoresponse of the CIGS/CdS heterojunction compared to bare CIGS films. The CIGS/CdS junction has also been tested in a PEC cell using a novel sulphide/sulphite electrolyte for the first time and found to yield further enhancement in photocurrent density with exceptional stability. Thus, apart from fabrication of an efficient CIGS/CdS heterojunction economically, the present study proposes use of a novel electrolyte yielding superior performance and showing potential for commercialization of CIGS devices and their use in photoelectrochemical cells.