Institute for Theoretical and Applied Electromagnetics RAS, Moscow 125412, Russia.
Sensors (Basel). 2022 Apr 18;22(8):3086. doi: 10.3390/s22083086.
Hollow ferromagnetic powders of iron were obtained by means of ultrasonic spray pyrolysis. A variation in the conditions of the synthesis allows for the adjustment of the mean size of the hollow iron particles. Iron powders were obtained by this technique, starting from the aqueous solution of iron nitrate of two different concentrations: 10 and 20 wt.%. This was followed by a reduction in hydrogen. An increase in the concentration of the solution increased the mean particle size from 0.6 to 1.0 microns and widened particle size distribution, but still produced hollow particles. Larger particles appeared problematic for the reduction, although admixture of iron oxides did not decrease the microwave permeability of the material. The paraffin wax-based composites filled with obtained powders demonstrated broadband magnetic loss with a complex structure for lesser particles, and single-peak absorption for particles of 1 micron. Potential applications are 5G technology, electromagnetic compatibility designs, and magnetic field sensing.
通过超声喷雾热解法获得了空心铁磁性粉末。通过改变合成条件，可以调整空心铁颗粒的平均粒径。通过该技术，从两种不同浓度的硝酸铁水溶液（10 和 20wt%）开始获得铁粉末，随后进行氢气还原。溶液浓度的增加会使平均粒径从 0.6 微米增加到 1.0 微米，并使粒径分布变宽，但仍能得到空心颗粒。较大的颗粒对还原来说是个问题，尽管添加氧化铁并没有降低材料的微波磁导率。用所获得的粉末填充的石蜡基复合材料表现出宽带磁损耗，对于较小的颗粒具有复杂的结构，而对于 1 微米的颗粒则具有单峰吸收。潜在的应用包括 5G 技术、电磁兼容性设计和磁场感应。
