本實驗使用三區爐管以化學氣相沉積法配合選擇性蝕刻，成功合成高寬比大於100的純相ZTO奈米線，並且使用氧化還原法將奈米銀粒子修飾在ZTO奈米線表面，形成半導體與金屬的異質接面，藉此探討ZTO在修飾後光催化性質變化。藉由PL以及UV-Vis進行光學檢測，ZTO奈米線的光致發光主要為氧空缺所貢獻的可見光，並且在修飾後奈米線的發光強度明顯減弱，證明銀粒子所造成的異質接面能有效降低電子-電洞對複合，並且降低的量隨修飾量增加而增加﹔由UV-Vis的吸收光譜轉換為Tauc Plot得知奈米線的能隙為4.01eV，並且在修飾後不會改變。以10ppm亞甲基藍作為降解液，ZTO奈米線經過120分鐘降解85%，1%Ag-ZTO經過120分鐘降解94%，，3%Ag-ZTO經過120分鐘降解96%，並且經三次循環降解後仍維持優異的光降解率，證明ZTO奈米線具有重複使用性以及結構穩定性。經由光催化抑制劑確認反應主要機制，抑制h+降解率由96%降至15%，抑制•OH降解率由96%降至52%，抑制•O2-降解率由96%降至63%，h+以及•OH為光催化主要反應物。

In this study, we use a three-zone furnace tube with chemical vapor deposition and selective etching to successfully synthesize pure phase Zn2SnO4 (ZTO) nanowires with an aspect ratio greater than 100, and use the Chemical bath redox method to modify different percentage of Ag nanoparticles on the ZTO nanowires. With optical detection by PL and UV-Vis, the luminescence intensity of the nanowires is significantly reduced after modification; the conversion from UV-Vis absorption spectrum to Tauc Plot shows that the energy gap of the nanowire is 4.01eV, and it will not change significantly after modification. Using 10ppm methylene blue as the degradation solution, ZTO nanowires degrade 85% after 120 minutes, 1% Ag-ZTO degrades 94% after 120 minutes, and 3% Ag-ZTO degrades 96% after 120 minutes, after three cycles of degradation the nanowires maintain an excellent photodegradation rate. The main mechanism of the reaction was confirmed by photocatalytic inhibitors, the inhibition of h+ degradation rate was reduced from 96% to 15%, the inhibition of OH degradation rate was reduced from 96% to 52%, h+ And • OH are the main reactant of photodegradation.

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