High dielectric and microwave absorption properties of ultra-thin 1-xSrTiO3-δ − xSrAl12O19 films

To reduce the thickness of the microwave absorbing materials, we have prepared 1-xSrTiO3-δ−xSrAl12O19 ceramics by hot−pressing sintering in the vacuum. The microstructure, dielectric, thermogravimetric analysis and microwave absorbing properties of 1-xSrTiO3-δ−xSrAl12O19 were systematically investigated and discussed. The 0.95SrTiO3-δ− 0.05SrAl12O19 has high permittivity, the real part is from 1662.2 to 704.9 and the imaginary part is from 208.6 to 12. The absorption bandwidth (reflection loss ≤−5 dB) of 0.95SrTiO3-δ− 0.05SrAl12O19 can cover 8.6 − 12.4 GHz and its thickness is only 0.232 mm which is much thinner than these recently reported by other researchers. For 0.942SrTiO3-δ− 0.058SrAl12O19, the peak value of reflection loss is up to − 58.5 dB with a thickness of 0.75 mm. The 1-xSrTiO3-δ−xSrAl12O19 films could be excellent candidates for highly efficient and ultra−thin microwave absorbing materials.