One-Pot Synthesis of Self-Stabilized Aqueous Nanoinks for Cu2ZnSn(S,Se)4Solar Cells

Copper zinc tin sulfide/selenide (CZTS/Se) is very promising for photovoltaic application because of their nontoxic, earth-abundant components and excellent optoelectronic properties. Herein, a novel in situ self-stabilization process using water as the only solvent is reported to produce CZTS nanoink. Aqueous processed metal chalcogenide complexes Sn 2 S 6 4– and Sn 2 S 7 6– were employed as the self-component ligands to in-situ cap the Cu/Zn sulfide nanoparticles, resulting in homogeneous and stable nanoinks. Through rational materials choice and annealing design, carbon, oxygen, and nitrogen contaminations were minimized in the final film. Finally, high quality CZTSSe film was integrated into a photovoltaic device achieving a preliminary solar conversion efficiency of 5.14%. The innovation of green, stable, scalable, and reliable quality aqueous CZTS nanoinks will further benefit the advancement of high-efficiency, low-cost CZTS solar cells.