尖晶石材料Fe1.495V1.505O4磁性、結構、與電荷轉移之交互作用研究

Study on the Interaction of Magnetism, Structure, and Charge Transfer in Spinel Material Fe1.495V1.505O4

呂家齊(CHIA-CHI LU)

指導教授 ： 楊仲準 ； 吳啟彬

中原大學/理學院/物理學系/碩士(2024年)

https://doi.org/10.6840/cycu202400450

摘要

過渡金屬氧化物(TMO) Fe1.5V1.5O4具有尖晶石之晶體結構特徵，且可以作為電池儲能與磁電材料使用。其材料應用性能與晶格結構、電性以及電荷分布相關。本研究首先以中子粉末繞射配合X光粉末繞射實驗進行材料的晶格結構及電荷分布研究,並鑑定出Fe1.5V1.5O4為四方晶系具空間群I 4 1 / a m d之結構。在3.3 K至450 K的溫度區間必沒有發現結構相變的產生。
而中子磁繞射分析則顯示Fe1.5V1.5O4的磁結構為磁矩略為偏離b軸之傾斜反鐵磁有序結構(Canted Antiferromagnetic ordering)，其磁空間群為I 4 1' / a m 'd，隨著溫度的上升，其磁矩會更加偏離b軸。直流磁化率實驗顯示了材料磁化強度呈現反鐵磁的現象，其磁相關溫度在400 K儀器量測極限之上。在磁滯曲線實驗顯示了中發現本材料在2 K時下具有明顯的磁叢現象。
比熱實驗顯示了本材料經典的Debye mode不同。可能是因為其具有自旋玻璃或是磁叢集的效應。

關鍵字

過渡金屬氧化物 ； 尖晶石 ； Fe1.5V1.5O4 ； 傾斜反鐵磁有序結構

並列摘要

The transition metal oxide (TMO) Fe1.5V1.5O4 exhibits characteristic spinel crystal structure features and has potential applications in battery energy storage and magnetoelectric materials. The performance of this material in such applications is related to its lattice structure, electrical properties, and charge distribution. In this study, neutron powder diffraction combined with X-ray powder diffraction was employed to investigate the lattice structure and charge distribution of the material, identifying Fe1.5V1.5O4 as having a tetragonal crystal system with space group I 4 1 / a m d. No structural phase transition was observed in the temperature range of 3.3 K to 450 K.
Neutron magnetic diffraction analysis revealed that the magnetic structure of Fe1.5V1.5O4 is a canted antiferromagnetic ordering with magnetic moments slightly deviating from the b-axis, corresponding to the magnetic space group I 4 1' / a m 'd. As the temperature increases, the magnetic moments deviate further from the c-axis. DC magnetization experiments showed an antiferromagnetic behavior, with the magnetic transition temperature being above the instrument's measurement limit of 400 K. The magnetic hysteresis experiments at 2 K demonstrated significant magnetic domain phenomena in the material.
Specific heat experiments indicated a deviation from the classical Debye model, possibly due to the presence of spin glass or magnetic cluster effects.

並列關鍵字

Transition Metal Oxide ； Spinel ； Fe1.5V1.5O4 ； Canted Antiferromagnetic ordering

參考文獻

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