Khalid Nouneh

Effect of substrate on ZnO thin films grown by SILAR method

Zinc oxide (ZnO) thin films were grown on three kinds of substrates (copper, silicon and glass) by the SILAR method. The solution was prepared by using zinc sulphate ZnSO4 and ammonia NH3. And for rinsing, we heated the distilled water at the temperature 80°C. The nature of substrate was found to have effect on the crystal structure, morphology and optical properties of the resultant ZnO thin films. For the X-ray measurements results, it can be see that growth orientation of the resultant ZnO thin films deposited on copper, silicon and glass substrates are (101), (103) and (002) respectively. The SEM results showed that the ZnO grains deposited on copper substrate takes the hexagonal structure, those deposited on silicon substrate takes the spindles shape, and who are deposited on glass substrate takes the forms of small flowers and prisms. XPS measurements were carried out, the result showed that the ZnO thin films grown on three kinds of substrates had different XPS behaviours. And one grown on the glass substrate had the best performance, and his gap close to 3.2 eV.

Electrochemical Lithium and sodium insertion from aqueous solutions into TiO 2 films deposited on stainless steel

Nanostructured titanium oxide thin films were fabricated directly by an anodic electrodeposition using an aqueous TiCl3 solution. Structure and morphology of thin layers of TiO2 deposited on stainless steel and annealed at different temperatures were characterized by X-ray diffraction (XRD) and microscopy techniques (SEM, AFM). Two phases of titanium oxide observed at annealing temperature 350 °C (rutile and anatase) converts after annealing at 450 °C into anatase well-crystallized phase. The grain size was of about 20-30 nm. By AFM analysis, roughness around 50 nm was observed. Cyclic voltammograms (CVs) showed that annealed titanium oxide films have exhibited reversible insertion/de-insertion of lithium ion and of sodium in LiOH or NaOH aqueous electrolyte.