Zn_(0.3)Fe_(2.7)O_(4)纳米颗粒可控合成及磁热性能研究  

Controllable synthesis and magnetothermal properties of Zn_(0.3)Fe_(2.7)O_(4)nanoparticles

作　　者：田大明 杨天宇 王浩雄 于杰 闫海涛[1] 贺淑莉[1] TIAN Daming;YANG Tianyu;WANG Haoxiong;YU Jie;YAN Haitao;HE Shuli(Department of Physics,Capital Normal University,Beijing 100048)

机构地区：[1]首都师范大学物理系,北京100048

出　　处：《首都师范大学学报（自然科学版）》2024年第2期95-102,共8页Journal of Capital Normal University：Natural Science Edition

基　　金：国家自然科学基金项目(52371257,51771124);北京市自然科学基金项目(Z190011)。

摘　　要：本文采用有机液相高温热分解方法,使用4-联苯羧酸作为表面活性剂,通过改变升温速率制备出了八面体、十四面体和星形3种形貌的Zn_(0.3)Fe_(2.7)O_(4)纳米颗粒,实现纳米颗粒形貌生长的可控合成。利用反相微乳液法将纳米颗粒包覆不同壳厚的SiO_(2),将其转为水溶性,并研究了Zn_(0.3)Fe_(2.7)O_(4)@SiO_(2)复合纳米颗粒在交变磁场下的比损耗功率(SLP)。结果表明:纳米颗粒的产热能力在高磁场强度下随SiO_(2)壳厚的增加而降低,而在低磁场强度下随SiO_(2)壳厚的增加而增加;随着SiO_(2)厚度的增加,磁性纳米颗粒之间的偶极相互作用减弱,由此引起的各向异性随之减小,导致磁性纳米颗粒在高磁场强度与低磁场强度下SLP有不同的变化规律。The octahedral,decahedral and star-like Zn_(0.3)Fe_(2.7)O_(4) nanoparticles were prepared by changing the heating rate,using 4-biphenyl carboxylic acid as a surfactant in the high temperature organic thermal decomposition synthesis,achieving controllable synthesis of nanoparticles morphology growth.Using the reverse microemulsion method,nanoparticles were coated with SiO_(2) of different shell thicknesses,making them water-soluble,and the specific loss power(SLP)of Zn_(0.3)Fe_(2.7)O_(4)@SiO_(2) composite nanoparticles under an alternating magnetic field was studied.The results indicate that the heat generation capacity of the nanoparticles decreases with increasing SiO_(2) shell thickness under high magnetic fields,while it increases with increasing SiO_(2) shell thickness under low magnetic fields.As the SiO_(2) thickness increases,the dipolar interactions between the magnetic nanoparticles are reduced,leading to a decrease in the resulting anisotropy.This causes SLP of the magnetic nanoparticles to exhibit different rules under high and low magnetic fields.

关 键 词：磁性纳米颗粒 高温有机合成 偶极相互作用 磁热性能 

分 类 号：O469[理学—凝聚态物理]