Synthesis, structural and photocatalytic characteristics of nano-Cu2−xSe

Large-scale synthesis of Cu2?xSe nanocrystals (nano-Cu2?xSe) with uniform size was performed via a facile hydrothermal method at room temperature and at 120??C. Nano-Cu2?xSe with different structures could be synthesized by changing the reaction/growth time, the Cu:Se molar ratios, and the initial concentration of the precursors. The synthesized nano-Cu2-xSe was characterized using various techniques, including x-ray powder diffraction, scanning electron microscopy and photocatalytic activity. Systematic studies showed that the reaction time played a key role in controlling the morphology and structure leading to significant influence on the photocatalytic activity of nano-Cu2?xSe. With increasing reaction/growth time, Cu2?xSe could transform gradually from a cubic to hexagonal structure and from nanoparticles to nanoplate/nanorod shapes. The photocatalytic characteristics were evaluated by the photo-decoloration of Rhodamine B (RhB) in aqueous solution under visible light irradiation. As-prepared nano-Cu2?xSe showed good photocatalytic activity under visible light irradiation, indicating potential applications in depollution technologies.