Paper Title
Nanocrystalline Cuingas2 (CIGS) Counter Electrode by Nebulizer Spray Technique for Dye-Sensitized Solar Cells

Abstract
Nanocrystalline CuInGaS2 (CIGS) counter electrodes were deposited with varying substrate temperature (250 oC, 300 oC, 350 oC and 400 oC) using nebulizer spray pyrolysis technique. The structural and crystalline parameters of CIGS thin film oriented along (1 1 2) plane were analyzed by XRD. The Raman spectra revealed the combined CA- and CH- orderings from the A1 mode at 296 cm-1. Surface morphology exhibited growth of uniform spherical grains with increase in temperature. The elemental composition and the chemical state of the nanocrystalline films were studied from XPS analysis. The p-type behavior, carrier concentration, mobility and electrical resistivity of the films were determined from the Hall effect and four probe measurements. The high electrocatalytic behavior was identified from cyclic voltammetry and electrochemical impedance spectroscopy. DSSC device was fabricated with the prepared nanocrystalline CIGS counter electrodes and the performance was evaluated from the current density–voltage (J-V) measurements. The CIGS CE prepared at 350 oC displayed maximum short-circuit current density (12.32 mA/cm2) and higher photon-to-current conversion efficiency of about 4.32%. Keywords - Nebulizer spray, CIGS, substrate temperature, Counter electrode, DSSC.