This article reports on Cu2ZnSnSe4 (CZTSe) thin film preparation via a nonhydrazine, nonpyridine and environmentally friendly low-cost solution process method. CZTSe fabrication through a solution-based process has not yet been suitably demonstrated given the impediments to addressing the presence of selenium in solutions. In this study, we introduced a two-step CZTSe fabrication method that used monoethanolamine as the chelating agent/co-solvent and ethanol as the main solvent. Selenization was then conducted. In this process, we successfully avoided the use of hydrazine to synthesise CZTSe thin films. Material characterisations (e.g. UV–VIS–NIR, scanning electron microscopy, electron dispersive spectroscopy, X-ray diffractometry and Fourier transform infrared spectroscopy) confirmed the high quality of the deposited thin films. The deposited CZTSe thin film showed high crystallinity without carbon …