• 한국자기학회지
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• 제17권2호
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• pp.76-80
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• 2007

화학기상응축공정법으로 세 가지 분해온도에서 제조된 나노 Fe-N 시료들을 뫼스바우어 분광기, XRD와 BET를 이용하여 자기적 특성의 변화를 연구하였다. 분해온도가 낮을수록 ${\gamma}'-Fe_4N$의 형성이 용이하였으며, 중간온도에서의 ${\epsilon}-Fe_{2.12}N$을 거쳐 높은 분해온도에서는 ${\gamma}-Fe$가 주로 형성되었다. 높은 분해온도에서는 Fe와 N이 서로 잘 결합되지 못하였는데, 이는 Fe와 N을 결합시키기 위해서는 분해온도를 낮게 하는 것이 바람직하다는 것을 의미한다.

• 한국입자에어로졸학회지
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• 제8권2호
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• pp.83-88
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• 2012

The electrical wire explosion process in liquid media is promising for nano-sized metal and/or alloy particles. The hybrid Pt/Fe-Cr-Al and Pt/Ni-Cr-Fe nanoparticles for exhaust emission control system are synthesized by electrical wire explosion process in liquid media. The alloy powders have spherical shape and nanometer size. According to the wire component, while Pt/Fe-Cr-Al nanoparticles are shown the well dispersed Pt on the Fe-Cr-Al core particle, Pt/Ni-Cr-Fe nanoparticles are shown the partially separated Pt on the Ni-Cr-Fe core particle. Morphologies and component of two kinds of hybrid nano catalyst particles were characterized by transmission electron microscope and energy dispersive X-ray spectroscopy analysis.

• 한국환경과학회지
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• 제25권4호
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• pp.517-524
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• 2016

In order to treat groundwater containing high levels of nitrate, nitrate reduction by nano sized zero-valent iron (nZVI) was studied using batch experiments. Compared to nitrate removal efficiencies at different mass ratios of $nitrate/Fe^0$, the removal efficiency at the mass ratio of 0.02% was the highest(54.59%). To enhance nitrate removal efficiency, surface modification of nZVI was performed using metallic catalysis such as Pd, Ni and Cu. Nitrate removal efficiency by Cu-nZVI (at $catalyst/Fe^0$ mass ratio of 0.1%) was 66.34%. It showed that the removal efficiency of Cu-nZVI was greater than that of the other catalysts. The observed rate constant ($k_{obs}$) of nitrate reduction by Cu-nZVI was estimated to $0.7501min^{-1}$ at the Cu/Fe mass ratio of 0.1%. On the other hand, TEM images showed that the average particle sizes of synthetic nZVI and Cu-nZVI were 40~60 and 80~100 nm, respectively. The results imply that catalyst effects may be more important than particle size effects in the enhancement of nitrate reduction by nZVI.