Ti-Ga 합금 위에 형성된 산화티타늄 피막의 광 전기분해 특성에 관한 연구

Photoelectrochemical Behaviour of Oxide Films on Ti-Ga2O3 Alloy

  • 박성용 (한국과학기술연구원 전기화학 연구실) ;
  • 조병원 (한국과학기술연구원 전기화학 연구실) ;
  • 윤경석 (한국과학기술연구원 전기화학 연구실) ;
  • 이응조 (고려대학교 금속공학과)
  • Park, Seong-Yong (Electrochemistry Lab.. Div. of Science & Engineering. KIST) ;
  • Cho, Byung-Won (Electrochemistry Lab.. Div. of Science & Engineering. KIST) ;
  • Yun, Kyung-Suk (Electrochemistry Lab.. Div. of Science & Engineering. KIST) ;
  • Lee, Eung-Cho (Dept. of Metallurgical Eng., Korea Univ.)
  • 발행 : 1992.12.31

초록

With the aim to obtain $TiO_2$ films with an increased photorespones and absorbance in the visible region of the solar spectrum, the direct oxidation of titanium alloys were performed. In this study, $Ti-Ga_2O_3$ alloy was prepared by mixing, pressing and arc melting of appropriate amounts of titanium and $Ga_2O_3$ powder. Electrochemical measurements were performed in three electrode cell using electrolyte of 1M NaOH solution. The oxide films on $Ti-Ga_2O_3$ alloy was composed of $Ti_2O$, TiO, $TiO_2$, $Ga_2TiO_5$. The free energy efficiency (${\eta}e$) of $Ti-Ga_2O_3$ oxide films had 0.8~1.3 % and were increased with the increase of $Ga_2O_3$ content up to 10wt %. The onset potential ($V_{on}$) had -0.8V~0.9V ranges and were shifted to anodic direction with the increase of $Ga_2O_3$ content. The spectral response of Ti-$Ga_2O_3$ oxides were similar to the response of the $TiO_2$ and their $E_g$ were observed to 2.90~3.0eV. Variations of onset potential($V_{on}$) associated with electrolyte pH were -59mV/pH. This probably reflects the nature of the bonding of $OH^-$ ion to the $TiO_2$ surface, a common phenomena in the transition-metal oxides.

키워드