Synthesis and characterization of CZTSe nanoinks using polyetheramine as solvent

This study developed a novel one-step method for the synthesis of well-dispersed CZTSe nanoparticles from Cu, Zn, Sn, Se elemental powders using a solvent-thermal reflux technique. Polyetheramine was used as a solvent and chelating agent, which provided two NH2 bonding sites at the ends as well as long, continuous epoxy chains in the center, making it ideally suited to the formation of CZTSe for use in ink printing. X-ray diffraction (XRD) and optical Raman spectroscopy were used to identify structural and phase information; transmission electron microscopy (TEM) and scanning electron microscopy (SEM) were used to confirm the morphology of the film as well as the shape and composition of the particles, and UV-Vis was used to characterize the band gap. We also investigated the composition and morphology of the CZTSe nanoparticles depending on different solvents polyetheramine and isophorondiamine. The polyetheramine-based process produced particles with far more Cu-poor and Zn-rich composition CZTSe phases, a smoother and closed packed morphology, and a more spherical crystal shape. In contrast, the isophorondiamine-based process produced nanoparticles with an irregular sheet-like shape. These results demonstrate that the solvent-thermal reflux method depends mainly on the structure of the chelating agent. The proposed technique is a low-cost and environmentally friendly solution-synthesis method applicable to the large-scale production of CZTSe for photovoltaic devices.