Manufacturing of Bi-functional Nano-sensor of Nobel Metal for Hydrocarbon Gas Detection in Petroleum Sector Using Pulse Laser Deposition Technique

Abstract

In the present investigation bi-functional nano-gas-sensor was manufactured from two types of metals: ZnO metal oxide and Pt noble metal. The nano-gas-sensors were designed for monitoring and control the environmental pollution in petroleum sector. The preparation technique was carried out by design and construction of a pulse laser deposition unit (PLD) with Nd: YAG laser (λ=532nm, laser fluence 2 J/cm2, repetition rate 6 Hz and the pulse duration 7ns). The target was pure ZnO and Pt:ZnO that containing 4%wt Pt. The hexachloroplatinic acid (H 2 PtCl 6 ) was used as Pt source. The PLD films were deposited at three different temperatures 200, 250, and 300 o C. Many characterization tests are used to study the influence of temperature on surface morphology of prepared films: Scanning Electron Microscope (SEM), Atomic Force Microscope (AFM), x-ray Diffraction (XRD) and (UV) visible. The results pointed to a direct relationship between the deposition temperature and the grain sizes of the nanoparticles formed on the substrate. On the other hand, the results of RMS roughness of AFM showed an increased value with increasing of deposition temperature. The best value of RMS roughness was 10.3nm for thin films deposited at 250ºC. The x-ray results shows formation of nanostructure on the substrate at deposition temperature of 250ºC, in which represent high surface area of gas sensor and especially with Pt. In addition, the UV-VIS transmittance measurements have shown that the films are highly transparent in the Visb-NIR wavelength region, with an average transmittance of about 90%. These results pointed to that the manufactured bi-metals nano-gas-sensor (Pt:ZnO) at 250 o C is more suitable for LPG hydrocarbons detection application in petroleum positions.