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.