Jbeli R, Boukhachem A, Ben Jemaa I, Mahdhi N, Saadallah F, Elhouichet H, Alleg S, Amlouk M, Ezzaouïa H
Laboratoire de Semi-conducteurs, Nanostructures et Technologies Avancées, Centre National de Recherches en Sciences des Matériaux, B.P. 95, Hammam-Lif 2050, Tunisia.
Unité de Physique des Dispositifs à Semiconduteurs, Faculté des Sciences de Tunis, Tunis El Manar University, Tunisia.
Spectrochim Acta A Mol Biomol Spectrosc. 2017 Sep 5;184:71-81. doi: 10.1016/j.saa.2017.04.072. Epub 2017 Apr 28.
Metal transition doped oxide thin films or nanocomposites have recently emerged at the forefront of potentials research. With the focus mainly on efficiency, the aspect of stability against optical irradiation of such materials has so far not been thoroughly addressed. This work covers the synthesis of silver doped lanthanum oxide thin films (LaO:Ag) which have been prepared by the spray pyrolysis technique on glass substrates at 460°C. Then, Ag thin films were grown on lanthanum oxide thin films by thermal evaporation. The present work aims to reach the synthesis of LaO:Ag thin films using both the spray pyrolysis and thermal evaporation techniques. First, X-ray diffraction analysis shows that undoped and Ag doped films crystallize in a mixture of hexagonal and cubic phase with crystallites oriented along (001) direction. Raman spectroscopy shows the bands positions corresponding to hexagonal and cubic phases. On the other hand, an attempt regarding their optical properties has been carried out by means of photoluminescence measurements. Second, from electrical conductivity measurements, the activation energy decreases from 1.42 to 1.09eV with the increase of annealing time and the charge carriers are following the CBH model as dominant charge transport mechanism. Finally, the annealing time influences the surface wettability property and transforms LaO character from hydrophobic (θ>90°) to hydrophilic (θ<90°).
金属过渡掺杂氧化物薄膜或纳米复合材料最近已成为前沿潜在研究领域。目前主要关注效率，而此类材料对光辐照的稳定性方面迄今尚未得到充分研究。这项工作涵盖了通过喷雾热解技术在460°C的玻璃基板上制备银掺杂氧化镧薄膜（LaO:Ag）。然后，通过热蒸发在氧化镧薄膜上生长银薄膜。本工作旨在利用喷雾热解和热蒸发技术合成LaO:Ag薄膜。首先，X射线衍射分析表明，未掺杂和银掺杂的薄膜在六方相和立方相的混合物中结晶，微晶沿（001）方向取向。拉曼光谱显示了对应于六方相和立方相的谱带位置。另一方面，通过光致发光测量对其光学性质进行了研究。其次，从电导率测量结果来看，随着退火时间的增加，激活能从1.42 eV降至1.09 eV，并且电荷载流子遵循CBH模型作为主要电荷传输机制。最后，退火时间影响表面润湿性，并将LaO的特性从疏水性（θ>90°）转变为亲水性（θ<90°）。
