A novel synthesis and optical properties of cuprous oxide nano octahedrons via microwave hydrothermal route

A novel and efficient synthesis of cuprous oxide (Cu2O) nano-octahedron was successfully prepared via a green chemie douce approach utilized a microwave hydrothermal route at low growth temperature without the presence of any surfactant. The crystalline structure of the Cu2O was characterized by several techniques like X-ray powder diffraction (XRD), Fourier transformation spectroscopy, field-emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy and transmission electron microscopy (TEM). XRD results indicate that the size of Cu2O nano-octahedron is 71 nm which is calculated with the help of Scherer equation, as supported by FESEM and TEM. The formation mechanism of the Cu2O octahedral was discussed. Optical absorption spectra reveal that the optical band gap of the Cu2O is controlled by quantum confinement effect. The obtained optical energy gap value E (g) of Cu2O octahedron was about 2.43 eV. The photoluminescence emission spectra of the Cu2O nano-octahedrons exhibit two emission peaks located at 342 and 365 nm due to the quantum effect. It is evaluated that the green chemie douce approach is a cheap and fast to synthesize Cu2O nano-octahedrons and could be potentially extended to other inorganic systems for industrial production.