本研究使用hexamethylenetetramine (HMT)作為摻雜來源，透過快速微波輔助水熱製程製得具有高比面積以及擁有可見光活性的碳或氮摻雜的二氧化鈦次微米球珠。在不同水熱溫度與持溫時間參數的影響下，次微米球珠所展現的形貌、尺寸、晶相結構、表面的化學鍵結形式、比表面積、光學等特性，本研究將會詳細的分析討論。從實驗結果可觀察到不具摻雜的次微米球珠其吸收邊緣座落在紫外光區；而碳或氮摻雜的二氧化鈦次微米球珠其吸收邊緣則有往可見光波長偏移的趨勢。本研究將得到的球珠作為光電極的材料並且組裝成完全可撓式的染料敏化太陽能電池(FDSCs)。藉由太陽光模擬器(solar simulator)、電化學阻抗分析(EIS)、intensity modu1ated photocurrent spectroscopy/photovoltage spectroscopy (IMPS/VS)、光電轉換效率分析(IPCE)來探討FDSCs的效能與光化學特性。此外，碳或氮摻雜次微米球珠光電極的總光吸收度以及染料分子的脫附量也可從UV-Vis分析結果計算得到。本研究使用碳或氮摻雜次微米球珠作為光電極其整體效率與IPCE的表現性確實比不具摻雜的次微米球珠和商用P25的光電極來的優異。

Carbon and/or nitrogen doped TiO2 submicrometer-sized beads with high surface areas and visible-light activity was systhesized using the hexamethylenetetramine (HMT) as dopant through a microwave-assisted hydrothermal synthetic route. The effects of hydrothermal temperature and reaction time on the characteristics of carbon and/or nitrogen doped TiO2 submicrometer-sized beads, such as size, crystallinity, surface oxidation state, specific surface area and optical properties, were studied. Compared to the undoped one, the absorbance edge of carbon and/or nitrogen doped TiO2 shifts towards a higher wavelength region. The resulting beads were employed as a new photoelectrode material for use in all-plastic flexible dye-sensitized solar cells (FDSCs). FDSCs were examined using solar simulator, electrochemical impedance spectroscopy (EIS), intensity modulated photocurrent spectroscopy (IMPS), intensity modulated photovoltage spectroscopy (IMVS) and incident photo to current conversion efficiency (IPCE). The total light absorbance and the amount of dye loading of the carbon and/or nitrogen doped TiO2 photoelectrode were also obtained. It was also found that the cells having a carbon and/or nitrogen doped TiO2 photoelectrode have better overall efficiency and IPCE compared to those based on undoped TiO2 beads and commercial P25.

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