초록 |
Recently, Hydrogen has attracted the attention of researchers to apply an industry field. However, H2 gas has characteristics of odorless, colorless and flammable at higher than 4 % in air. Conventional H2 detection sensors have limits of about malfunction, electrical drive and cost. Therefore, new detection method to find easily H2 leak is necessary like using color change in the presence of H2 gas. WO3 is well known as an electrochromic material to change color from transparent to dark blue. The combination of WO3-Palldaium (Pd) hybrid was used for the H2 sensor. RF magnetron sputtering to deposit WO3 was performed on glass substrate at room temperature. Prepared WO3 revealed porous columnar-structure and the thickness is measured to 600 nm by scanning electron microscopy. X-ray diffraction patterns showed that prepared WO3 possesses amorphous. E-beam evaporation was conducted to form Pd nanoparticles on WO3 thin films. The thickness and morphology of Pd was observed by using transmission electron microscopy. UV-visible spectrum showed transmittance change from 60 to closely 5 % at the visible region after 5 min in the presence of 1% H2 gas. Color difference (ΔE) was utilized to quantify real color change and measured to be 30 after 5 min at same H2 condition. In conclusion, we optimized the columnar porous structure of WO3 and achieved intense color change. |