HF, NaF, NH4F와 같이 플루오르 이온(F-)이 함유된 전해질에서 티타늄 금속판을 양극산화시켜 0.34 μm부터 최대 8.9 μm까지 다양한 길이의 티타니아 나노튜브(TNT)를 제조하였다. 양극산화에 의해 제조된 TNT를 450 °C에서 소성시키면 광 활성을 가지는 아나타제 결정이 생성되었다. TNT 기반 염료감응 태양전지(DSSC)는 TNT 길이가 2.5 μm일 때 광전환 효율이 4.71%로 최대를 나타내었다. 이 값은 티타니아 페이스트를 코팅하여 제작한 FTO 기반 DSSC의 광전환 효율 보다 약 18% 높았다. 또한 TNT-DSSC의 단락전류밀도(Jsc)는 9.74 mA/cm2로 FTO-DSSC의 7.19 mA/cm2 보다 약 35% 이상 높았다. TNT-DSSC 태양전지의 광전환 효율이 더 높은 이유는 염료에서 생성된 광전자가 TNT를 통해 전극 표면으로 빨리 전달되어 광전자와 염료가 재결합 되는 것이 억제되었기 때문이다.

Titanium nanotubes (TNT) of various lengths ranging from 0.34 °C to a maximum of 8.9 °Cwere prepared by anodizing a titanium metal sheet in an electrolyte containing fluorine ion (F-) of HF, NaF and NH4F. When TNT prepared by anodizing was calcined at 450 °C, anatase crystals with photo activity were formed. The TNT-based dye-sensitized solar cell (DSSC) showed a maximum conversion efficiency of 4.71% when the TNT length was 2.5 μm. This value was about 18% higher than photo conversion efficiency of the FTO-based DSSC coated with titania paste. And the short circuit current density (Jsc) of the TNT-DSSC was 9.74 mA/cm2, which was about 35% higher than the 7.19 mA/cm2 of FTO-DSSC. The reason for the higher conversion efficiency of TNT-DSSC solar cells is that photoelectrons generated from dyes are rapidly transferred to the electrode surface through TNT, and the recombination of photoelectrons and dyes is suppressed.

DSSC Titania nanotube Anodizing

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