本實驗使用三區爐管以熱蒸鍍法製備形貌優異的氧化鉬奈米線，第二階段以化學氣相沉積法將氧化鉬奈米線硫化，製備出氧化鉬-硫化鉬核殼奈米線。將兩種奈米線以SEM、XRD、TEM、EDS、XPS觀察形貌以及分析晶相，確認本實驗所合成之奈米線皆含有氧空缺。第三階段將兩種奈米線做電性以及光催化實驗，將其與文獻做比較。電性量測發現氧化鉬奈米線電阻率為6.3*10-7 Ω-m，低於文獻值，推測為氧空缺的形成導致電性的提升；氧化鉬-硫化鉬核殼奈米線的電阻率為1.65*10-4Ω-m，大於文獻值，推測是核殼結構造成整體載子濃度下降且S2-原子佔據氧空缺，使氧空缺數量下降。光降解性質量測發現氧化鉬奈米線在可見光照射60分鐘得降解效率為22%，相較完整化學量比的三氧化鉬晶體效率高；氧化鉬-硫化鉬核殼奈米線在可見光照射60分鐘的降解效率為34%，相較文獻中對二氧化鉬要透過紫外光才能進行降解，且降解效率僅有22%，因此以上性質顯示兩種奈米線在光電元件有發展的潛力。

In this experiment, a three-zone furnace tube was used to prepare molybdenum oxide (MoO3-x) nanowires by thermal evaporation. In the second part, MoO3-x nanowires were sulfurized to molybdenum disulfide (MoS2) to synthesis MoO2-MoS2 core-shell nanowires via chemical vapor deposition (CVD). The morphology and phase of two kinds of nanowires were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray spectroscopy (EDS), and it was confirmed that the nanowires synthesized in this experiment contained oxygen vacancies. Photodegradation studies show that under visible light irradiation for 60 mins, the degradation efficiency of the MoO3-x nanowires was 22%, higher than that of the MoO3 crystals in previous reports, while the degradation efficiency of MoO2-MoS2 core-shell nanowires was 34%, higher than that of MoO2 nanoparticles in previous works. Additionally, the resistivities of a MoO3-x nanowire and a MoO2-MoS2 core-shell nanowire were measured to be 6.3*10-7 Ω-m and 7*10-4 Ω-m, respectively. The results show that the two types of nanowires have potential in electronic devices, sensors, solar cells, chromic devices and photocatalyst in the future.

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