摻氮二氧化鈦在可見光下分解氣相丙酮

Oxidation of Gaseous Acetone with Nitrogen-Doped Titanium Dioxide Illuminated by Visible Light

光觸媒二氧化鈦（TiO2）常裝設於空氣清淨機，用於室內淨化空氣品質，提升居家環境健康。本研究採用溶膠-凝膠法（sol-gel）摻氮結合水熱法製備TiO2，以日光燈為光源，探討觸媒製備因子（N/Ti比例、水熱溫度、水熱時間）對光觸媒活性之影響。觸媒特性以X光繞射儀（XRD）與場發射掃描電子顯微鏡（FE-SEM）分析。實驗結果顯示N/Ti比例越高，丙酮殘餘率越低，最佳N/Ti比例為1.8%。經水熱法處理TiO2比未經過水熱法處理TiO2擁有更高的光催化效果；水熱溫度250oC的TiO2活性最高，水熱時間1hr、2hr、5hr的觸媒丙酮殘餘率較低，當水熱時間增至12hr以上，丙酮殘餘率增加。以TiO2摻氮加水熱法，可以提升TiO2在日光燈下光降解氣相丙酮的活性。

The photocatalytic air purifier can convert toxic gases into safer compounds in indoor. I n this study, th e sol-gel method combining with hydrothermal process was used to prepare N-doped TiO2 . This experiment used the visible light as light souse to degrade gaseous acetone by photocatalysis, in order to explore the effect of the prepared factors such as N/Ti ratio, hydrothermal temperature and hydrothermal time. The characteristics of photocatalyst were analyzed by X-Ray diffraction and Field-emission scanning electron microscope. The residual rate of acetone and the concentration of CO2 were analysed. N-doped TiO2 obviously reduced the residual rate of acetone comparing with the pure TiO2 . In addition, when N-doped TiO2 was treated by hydrothermal process, the photocatalytic activity was higher than the N-doped TiO2 without the treatment of hydrothermal process. The photocatalytic activity of TiO2 with hydrothermal temperature at 250 o C was higher than that of TiO2 with other hydrothermal temperature. The photocatalyst with hydrothermal time less than 5hr showed lower acetone residual rate, and the residual rate of acetone was increasing with the hydrothermal time. The results demonstrated that N-doped TiO2 combining with hydrothermal process could increase the activity of TiO2 to degrade gaseous acetone under a fluorescent lamp.