Effect of PVA concentration on microwave absorption properties of ZnO nanofibers prepared by electrospinning

Abstract

ZnO nanofibers were prepared by electrospinning method in this work. The effects of PVA concentration on the morphology, dielectric properties and microwave absorption properties of ZnO nanofibers were studied. Results show that with the concentration of PVA increases from 6% to 10%, the diameter of ZnO nanofibers becomes smaller, but the knots increase and the thickness is uneven. When the concentration of PVA is 8%, ZnO nanofibers show the best morphology with fine and uniform diameter, smooth surface and less knots. At this point, the complex permittivity of it reaches the highest value with a real part of 15.4-20.8 and imaginary part of 3.6-4.7. It also has an optimum microwave absorption property in a thinner thickness. When the thickness of 70%ZnO nanofiber/paraffin sample is 1.3 mm, the microwave absorption bandwidth of reflection loss below –5 dB reaches 5.4 GHz (12.6-18 GHz), the minimum reflection loss is –16.6 dB. In addition, the content of paraffin also has an important effect on the dielectric property and microwave absorption property of the sample. The complex permittivity of the sample decreases as increasing the content of paraffin. When the content of paraffin is 30% and 20%, the samples have good microwave absorption properties.

Keywords

• electrospinning
• zno nanofibers
• dielectric property
• microwave absorption property