Liquid-Phase Pulsed Laser Ablation and Electrophoretic Deposition for Chalcopyrite Thin-Film Solar Cell Application

We report ligand-free synthesis of colloidal metallic nanoparticles using liquid-phase pulsed laser ablation, and electrophoretic deposition of the nanoparticles for fabrication of Cu(In,Ga)Se-2 (CIGS) thin film solar cells. First, colloidal metallic nanoparticles of Cu-In and Cu-Ga alloys are produced by pulsed laser ablation in common organic solvents without using stabilizing ligands. The nanoparticles are examined for phase, composition, and electrical surface charging and charge modulation mechanisms. Metallic precursor thin films with high purity and precise composition are produced by electrophoretic deposition of the colloids without transferring to another solvent and without using binders. Finally, we demonstrate fabrication of CIGS solar cells on Mo sheet substrates with an (active area) energy conversion efficiency up to 7.37%.