Lightweight SrM/CCTO/rGO nanocomposites for optoelectronics and Ku band microwave absorption

In this research, nanocomposites comprising M-type strontium hexaferrites (SrM) SrFe12-xCsxO19 (x=0.0, 0.05, 0.10), calcium copper titanate (CCTO) CaCu3Ti4-yAlyO12 (y=0.0, 0.1, 0.2) and reduced graphene oxide (rGO) have been prepared. XRD patterns shows the presence of single phase nanocrystalline SrM and CCTO which is further supported by Raman spectroscopy and FTIR analysis. The presence of secondary phase such as -Fe2O3, CaTiO3, and CuO has not been observed. Characteristics absorption bands of Cs-substituted SrM and Al-substituted CCTO were observed at 446, 551 and 605cm(-1), these peaks gives the idea of the formation of SrM and CCTO phase. The D and G bands of GO were observed at 1358 and 1604cm(-1) respectively, while that of the rGO were respectively observed at 1351 and 1595cm(-1). FESEM micrographshow the incorporated SrM nanoparticles, CCTO nanoparticles and rGO sheets, reduction in surface energy and magnetic dipolar interaction prompt the SrM nanoparticles to surround the CCTO nanoparticles and decorate the surface of the rGO sheets. The non-magnetic CCTO phase in the nanocomposites causes the tuning ofthe magnetic properties. The band gap obtained from UV-vis NIR spectroscopy is within the range of UV-blue LED application. The sample SCR3 shows a maximum reflection loss of -16.0dB at 18.0GHz and matching thickness of 2mm. The obtained reflection lossis attributedto multiple absorption mechanism as a result of improved impedance matching between the dielectric and magnetic loss absorbents.