兩種不同方法產生的奈米銀微粒之形態特性分析

Characterizations of Silver Nanoparticles Generated from Two Different Methods

曾能駿(Neng-Chun Tseng) ； 武紅幸(Hong-Hanh Vu) ； 陳俊瑋(Chun-Wei Chen) ； 陳春萬(Chuen-Wann Chen) ； 蔡春進(Chuen-Chin Tsai)

《勞工安全衛生研究季刊》 22卷2期 (2014/06) Pp. 158-168

摘要

本研究使用蒸發／冷凝法與恆定霧化法產生奈米銀微粒，並利用微分電移動度分徑器（Differential Mobility Analyzer, DMA）篩選出30~300nm的單徑銀微粒，再以高溫爐改變其形貌，研究單徑微粒的電移動度粒徑（mobility diameter, d_m）、質量、有效密度以及肺胞區沉積表面積濃度的變化。結果顯示兩種微粒產生法的d_m變化都可以分為三個階段：蒸發／冷凝法在第一階段燒結溫度24~100℃時奈米微粒燒結情況不明顯，d_m稍微變小；第二階段燒結溫度100~200℃，d_m快速變小，燒結情況明顯，微粒也趨於橢圓狀；第三階段燒結溫度200~800℃，微粒粒徑變化不大，但微粒形貌持續改變且最後變成圓球狀。噴霧法所產生的銀微粒則會受到界面活性劑的影響，在燒結溫度大於400℃以上，因界面活性劑的蒸發，d_m才有明顯的變化。由蒸發／冷凝法與恆定噴霧法所產生出的微粒的形貌差異非常大，前者產生的微粒是由許多原始微粒團聚而成且呈不規則狀，後者所產生出的銀膠微粒大部分都被界面活性劑所包覆並且接近圓球狀，因而造成兩種微粒的表面積形狀因子、動力形狀因子、微粒有效密度的差異。

關鍵字

蒸發／冷凝法 ； 恆定霧化法 ； 奈米銀微粒 ； 動力形狀因子 ； 微粒有效密度

並列摘要

In this study, the silver agglomerates and silver colloids were generated by evaporation/condensation method and constant output atomizer. The differential mobility analyzer (DMA) was uased to classify the monodisperse particles with mobility diameters of 30, 80, 150, 250 and 300 nm, and then sintered by second furnace from 24 to 800˚C. The scanning mobility particle sizer (SMPS), aerosol particle mass analizer (APM), Aerotrak 9000 were used to measure the particulate size distribution, mass, alveolar deposited surface area concentration, respectively. Agglomerates are sampled using the microorifice-based concentrated nanoparticle sampler (CNS) and then analyze by TEM. The results showed that number median diameters (NMDs) of silver agglomerates were significantly reduced for sintering temperature from 100 to 200˚C, but showed little variation for sintering temperature above 200˚C. And NMDs of silver colloids were significantly changed for sintering temperature above 400˚C due to the surfactants. The silver agglomerates generated by evaporation/condensation method were found to be irregular and composed of several primary particles as observed by the TEM images. However, silver colloids generated by constant output atomizer were covered with the surfactant and presented spherical shape which result in the differences in surface shape factor, dynamic shape factor and particle effective density.

並列關鍵字

Evaporation/condensetion method ； Constant output atomizer ； Alveolar deposited surface area concentratio

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