LAUSR

Abstract A one-pot synthesis of novel hierarchical flower-like Cu 7.2 S 2 Se 2 nanocrystals was developed based on the direct metal surface elemental reaction (DMSER) method. This new room temperature synthesis is an economic and environmentally friendly soft chemical approach. The prepared Cu 7.2 S 2 Se 2 nanocrystals uniformly cover the surface of the Cu substrates. The mechanism of formation was investigated by observing the materials produced from changing the reaction time, the molar ratio of Na 2 S to elemental selenium, and the volume of solvent. The crystal structure, surface morphologies and light absorption properties were collected by X-ray diffraction (XRD), field emission scanning electron microscopy (SEM), transmission electron microscopy (TEM), and UV–visible spectroscopy. The results show that the as-prepared ternary nanocrystals are face-centered cubic and have an optical bandgap of 1.58 eV, which is ideal for potential solar cell applications. Transient photovoltage spectroscopy (TPV) was used to evaluate the photovoltaic performance of pure Cu 7.2 S 2 Se 2 nanocrystalline powder as well as in-situ generated Cu 7.2 S 2 Se 2 /ZnO heterojunctions. The current work offers a novel and simple approach for preparing ternary chalcogenide semiconductors for photoelectric and photocatalytic applications.