Nanocrystalline Pt-doped TiO sub(2) thin films prepared by spray pyrolysis for hydrogen gas detection

• Published in: Bulletin of materials science 2014-05, Vol.37 (3), p.425-432
• Main Authors: Patil, Lalchand A, Suryawanshi, Dinesh N, Pathan, Idris G, Patil, Dhanashri G
• Format: Article
• Language: English
• Subjects: Aqueous solutions; Ethyl alcohol; Materials science; Nanostructure; Platinum; Spray pyrolysis; Thin films; Titanium dioxide
• ISSN: 0250-4707; 0973-7669
• DOI: 10.1007/s12034-014-0705-y

Nanostructured pure and Pt-doped TiO sub(2) thin films were prepared by chemical spray pyrolysis technique. Aqueous solution of TiCl sub(3).6H sub(2)O (0.01 M) was chosen as the starting solution for the preparation of pure TiO sub(2) thin film. Aqueous solutions of PtCl sub(6).6H sub(2)O (0.01 M) and TiCl sub(3).6H sub(2)O (0.01 M) were mixed in volume % of 1 : 99, 2.5 : 97.5 and 5 : 95 respectively to obtain Pt-doped TiO sub(2) thin films. The solutions were sprayed onto quartz substrate heated at 350 degree C temperature to obtain the films. These thin films were fired for one hour at 550 degree C. The sensing performance of these films was tested for various gases such as LPG, H sub(2), CO sub(2), ethanol, NH sub(3) and Cl sub(2) (1000 ppm). The Pt-doped TiO sub(2) (1 : 99) was observed to be most sensitive (572) to H sub(2) at 400 degree C with high selectivity against other gases. Its response time was short (10 s) and recovery was also fast (14 s). To understand the reasons behind the gas-sensing performance of the films, their structural and microstructral properties were studied using X-ray diffraction and electron microscopy (FE-SEM and TEM), respectively. Thicknesses of all these samples were determined using Surface Profiler. The results are interpreted.