為了提高氧化鎢奈米線之光催化與氣體傳感器之性能並增加實際之應用價值，嘗試以外來金屬之摻雜降低材料能階，並形成散射中心防止電子電洞對再結合，氧化鎢奈米線的高體表面積比亦使得催化效果提升成為可能。本實驗以鮮少人使用之摻雜方法，透過CVD法以單一步驟成功製備高結晶度之錳摻雜與鉀摻雜之氧化鎢奈米線，藉由控制沉積溫度、持溫時間、前驅物量、載流氣體流量得到高線密度生長之金屬離子摻雜氧化鎢奈米線，並透過SEM觀察形貌、TEM求得晶面間距、EDS分析元素組成、XRD鑑定結構、XPS分析化學價態、PL檢測材料發光波段，接著量測錳摻雜與鉀摻雜之單根奈米線之電阻率分別為1.81*10-5 Ω·m、1.93*10-5 Ω·m，比未摻雜之8.27*10-6 Ω·m高出許多，證實了摻雜導致電阻率上升之效應。有趣的是，摻雜導致了氧化鎢奈米線由單斜晶至亞穩定態之六方晶之相轉變，其結構以六邊形之電子通道而聞名。雜質原子的引進降低了電子電洞對再結合之速率，而六方晶結構帶來電荷的有效傳輸，提升氧化鎢奈米線之催化效率，這使得錳摻雜之氧化鎢奈米線在對亞甲基藍進行四個小時之降解後，催化效率高達98.5%，鉀摻雜之氧化鎢奈米線也高達97.73%，接著對濃度為20ppm之乙醇在不同溫度下進行氣體感測研究分析，結果顯示出摻雜程度對氣感響應之正向相依性，在250oC時，錳摻雜與鉀摻雜之響應比原本未摻雜之響應分別高出了14.4%、29.7%，因此，以上性質揭示了所合成出的錳摻雜與鉀摻雜氧化鎢奈米線是成為光催化與氣體感測潛力材料的極佳候選者。

In this experiment, high crystallinity manganese doped and potassium doped tungsten oxide nanowires were successfully prepared by CVD method. The structure and composition of the nanowires are characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Interestingly, the doping leads to the phase transition from monoclinic to metastable hexagonal tungsten oxide nanowires, whose structure is known for its hexagonal electron channels. The introduction of impurity atoms reduces the rate of electron-hole pair recombination, while the hexagonal structure provides efficient charge transfer and enhances the catalytic efficiency of the tungsten oxide nanowires, which resulted in a catalytic efficiency of 98.5% for the manganese doped tungsten oxide nanowires and 97.73% for the potassium doped tungsten oxide nanowires after four hours of degradation of methylene blue. Also, the results of gas sensing response for 20 ppm ethanol showed a positive dependence of doping, with the manganese doped and potassium doped response being 14.4% and 29.7% higher than the original un-doped response at 250oC. Therefore, the above properties reveal that the synthesized manganese doped and potassium doped tungsten oxide nanowires are excellent candidates for photocatalytic and gas sensing potential materials.

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