Photoluminescence properties of rod-like Ce-doped ZnO nanostructured films formed by hot-water treatment of sol–gel derived coating

Rod-like undoped and Ce-doped ZnO nanostructures have been formed using hot-water treatment of the undoped and Ce-doped sol–gel derived layer at low temperature of 60 °C for 30 min on glass substrates. The concentration of Ce doping was varied from 2 to 20 at% in the precursor films. Morphological structures and optical properties of the hot-water treated ZnO films were investigated and compared with those of the conventional, annealed ZnO films. The resultant undoped and Ce-doped rod-like ZnO films showed ultraviolet (UV) and strong blue emissions. The photoluminescence of the Ce-doped films exhibited blue shift in UV emission and reduced blue emission intensity, compared to pure ZnO due to the incorporation of Ce. Increment of broad green emission intensity is observed with increased Ce doping in the precursor concentration for the hot-water treated films, which indicates the formation in Ce vacancies. Ce-doped ZnO films obtained which show promising optical properties can be used for the fabrication of optoelectronics devices utilizing substrates with low thermal stability such as organic polymers.

► Rod-like Ce-doped ZnO nanostructures were formed by hot-water treatment.
► The photoluminescence of the annealed and hot-water treated films are compared.
► Ultraviolet and visible emissions are observed for hot-water treated films.
► Hot-water treated Ce-doped films exhibit blue shift of UV and stronger green emissions.