Production and microwave electromagnetic shielding effectiveness of polyaniline-la₂ti₂o₇:Er,yb composites

In this research, La₂Ti₂O₇ doped with erbium-ytterbium was produced by using solid state technique. A series of compounds with the chemical equation (La_1−x−yRE_x−y)₂Ti₂O₇ were doped with (Er³⁺, x = 0.025, 0.050 ) and (Yb3+ y = 0.02 ) rare earth ions prepared by conventional solid state reaction method at 1350^oC for 24 h. X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) were carried out for the structural analysis, which showed that second phase did not form in (La_1−x−yRE_x−y)₂Ti₂O₇. Additionally, the polyaniline-erbium, ytterbium doped La₂Ti₂O₇ composites were fabricated via hot pressing using the compositions of (La_0.955Yb_0.02Er_0.025)₂Ti₂O₇, (La_0.93Yb_0.02Er_0.05)₂Ti₂O₇ and aniline. The weight ratios of erbium-ytterbium doped lanthanum titanate and aniline were 1:1 and 1:3 respectively, and epoxy resin was utilized to develop microwave shielding effectiveness composites. The microwave shielding effectiveness performances of polyaniline-La₂Ti₂O₇: erbium-ytterbium composites were examined by shielding effect in 0-8 GHz using two-port vector network analyzer. A minimum of-34.37 dB shielding effect performance was obtained in 6.27 GHz at the thickness of 2.0 mm. This shielding effect performance can be adjusted easily by managing the content of polyaniline in the composites for the needed frequency bands.