Growth and properties of titanium oxide nanostructure prepared by oxidation of titanium through joule heating under oxygen atmosphere

• Main Authors: Kang-Shyuan Peng, 彭康縣
• Other Authors: Jih-Shang Hwang
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/73707462719022980399

碩士 === 國立臺灣海洋大學 === 光電科學研究所 === 100 === With current flowing though Ti sheets to heat the sheets in oxygen atmosphere, we have successfully grown a black titanium dioxide (TiO2) nanostructure on titanium sheets. The photochemical (PEC) water splitting (WS) efficiency of the black TiO2 reached 0.82% (0.23V bias); in contrast, the PEC WS efficiency attained on TiO2 films grown by furnace heating of Ti sheets in oxygen atmosphere showed only 0.06%. XPS analysis showed that the black titanium oxide contains Ti-O-H bonds, which agrees well with the black TiO2 powders prepared by hydrogenation of TiO2 powder in the literature. We also found that the thickness of the Ti sheet plays an important role in the adhesion condition of the TiO2 nanostructures due to the difference in thermal expansion coefficient between TiO2 anf Ti sheet. The TiO2 structure would be peeled off if the thickness of the Ti sheet is too thick; however, it would lose its support if the sheet is too thin. A thickness of 0.25mm was found optimal for growth of the black TiO2 for PEC WS. Our experimental results show clearly bubbles of H2 and O2 mixture generated under AM 1.5G illuminations. The H2 production rate was estimated to be 1.67cc/hour.