Hydrophilic nickel doped porous SnO <sub>2</sub> thin films prepared by spray pyrolysis
Mehdi Khalfallah, Noubeil Guermat, Warda Daranfed, N. Bouarissa, Haddi Bakhti
Abstract
Abstract This work deals with the preparation and characterization of pure and Nickel-doped porous Tin oxide (SnO 2 ) thin films, using Spray pyrolysis technique for an eventual application in optoelectronics. The structural, morphological, optical, and electrical properties of these prepared samples were investigated using various techniques. X-ray diffraction analysis confirmed the tetragonal structure of pure SnO 2 and Ni-doped films. The preferred orientation of the crystallites changed from (110) to (200) with the film doped at 15.3 at.% Ni, with crystallite size of about 10 and 18 nm for 15.3 at.% Ni-doped and 5.6 at.% Ni-doped SnO 2 , respectively. Scanning Electron Microscopy shows that the 15.3 at.% Ni-doped SnO 2 film surface is relatively homogeneous, while the 5.6 at.% Ni-doped film is highly porous. The measured contact angles are less than 90° for all the prepared samples confirming the hydrophilic character of all the films. Transmittance as high as 85% in the visible region was observed for 5.6 at.% Ni-doped films, while lower transmittance is observed for 15.3 at.% Ni-doped films. A decrease of the optical band gap and the resistivity with increasing Ni dopant concentration were also observed.