Economic pulse electrodeposition for flexible CuInSe2 solar cells

Electrodeposition is one of the leading non-vacuum techniques for the fabrication of CuInSe₂ (CIS)-based solar cells. In the present work, pulse electrodeposition, an advanced technique, is utilized effectively for CIS absorber preparation devoid of any additives/complexing?agents. An economic pulse electrodeposition is employed for the deposition of Cu/In stack followed by selenization to fabricate CIS absorbers on flexible and glass substrates. The approach uses a two-electrode system suitable for large area deposition and utilizes the fundamentals of pulse electrodeposition with appropriate optimization of parameters to obtain smooth Cu/In precursors. The selenized CIS absorbers are of 1?μm thick while possessing copper-poor composition (Cu/In ≈ 0.9) and tetragonal chalcopyrite phase. The fabricated devices have exhibited a power conversion efficiency of 5.2%. The technique can be further improved to obtain low-cost CIS solar cells which are suitable for various small-scale energy applications.