Copper oxide nanoparticles doped with lanthanum, magnesium and manganese: optical and structural characterization

Copper oxide (Cu 2 O) is a promising semiconductor for photovoltaic and photocatalytic applications since this material has a high optical absorption coefficient and lower band gap (2.17 eV). Doped lanthanum (La), magnesium (Mg) and manganese (Mn) Cu 2 O nanoparticles (Cu 2 O Nps) were prepared by a displacement reaction. The doped and undoped Cu 2 O Nps were characterized with scanning electron microscopy–energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), transmission electron microscopy (TEM) and ultraviolet–visible spectroscopy. The EDS results confirm the presence of La, Mg and Mn in the Cu 2 O Nps. The XRD results confirm the formation a single cubic phase of Cu 2 O with a cuprite structure. TEM images confirm the formation of Nps with mean diameters between 12.0 ± 6.1 and 30.8 ± 11.0 nm. Doped and undoped Nps present a narrow band gap (2.40 eV), blue shifted with respect to bulk Cu 2 O.