鎳鋅鐵氧磁體奈米粒子生成動力學及其電磁波吸收行為之研究

The Kinetics and Electromagnetic-Wave Absortion Material of Crystallization of Nanosized Ni-Zn ferrite Powders Prepared by the Hydrothermal Method

孔守中(Shong-Chung Kung)

指導教授 ： 王宏文

中原大學/理學院/化學研究所/碩士(2003年)

https://doi.org/10.6840/cycu200300263

摘要

摘要
本研究主要是以Ni-Zn 鐵氧磁體材料為主，以水熱法製備奈米級Ni-Zn鐵氧磁粉並嘗試以水熱反應過程中的實驗條件(如:溫度,時
間,pH值,溶劑等…)控制其粒子所形成的大小。並以Arrhenius equation計算水熱法製備Ni-Zn Ferrite時的活化能為56.19Kj/mole。由結果顯示隨著水熱反應時間的增加、溫度的上升、溶劑極性的增加，粉體的結晶性較好，粒徑也相對的較大。
以氧化物混合法製備Ni-Zn Ferrite添加5wt%之三種金屬元（Co、
Cu、V2O5）與水熱法所製備的粉末比較，以獲得不同粒徑大小及不
同摻雜，對電磁波吸收的關係及影響；將試片厚度控制在5mm時，
米級粉體其電磁波吸收的段較高，約在6GHz左右，有-25dB的吸收；
當粉體粒徑增加時，其吸收的頻段會隨之降低，約在2GHz時可達到
-25dB的吸收效果。

關鍵字

鐵氧磁體 ； 電磁波 ； 水熱法

並列摘要

Abstract
Nanosized powders of Ni0.5Zn0.5 Fe2O4 with well-developed spinel phases were prepared by the hydrothermal method. An average particle size about 10 ~ 20 nm of Ni-Zn ferrite powder is obtained. The crystallization of the spinel ferrites was promoted by the increase of reaction temperature and time. The activation energy for this process is calculated around 56.19 kJ/mol.
The electromagnetic properties of these materials, namely permittivity and permeability were measured in 0.8-3GHz and 2-15GHz frequency range. Ni-Zn ferrite reflection losses achieve the satisfactory value of –25dB at 6GHz when particle size about 12nm, with the increase of the particle size the microwave absorption frequency are shift to 2GHz for the thickness of 5mm.

並列關鍵字

Electromagnetic-Wave ； ferrite ； hydrothermal

參考文獻

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