Dielectric, magnetoelectric and magnetodielectric properties in CMFO-SBN composites

摘要

The paper reports synthesis of Sr_(0.5)Ba_(0.5)Nb_2O_6 (SBN) and Co_(1.2-x)Mn_xFe_(1.8)O_4 (CMFO) via ceramic and hydroxide co-precipitation routes respectively. The nanopowders of SBN-CMFO0.1 (MSBN0.1) and SBN-CMFO0.3 (MSBN0.3) are compacted to form the desired magnetoelectric (ME)/magnetodielectric (MD) composites. The Bi_2O_3 is used as a sintering aid. The Bi_2O_3 at three weight percent is observed to cause agglomeration of SBN and CMFO particles and improve the magneto-mechanical coupling. The composites are investigated for their ferroelectric, ferromagnetic, dielectric, magnetoelectric (ME) and magnetodielectric (MD) properties. The results on the magnetocapacitance (M_c) are observed interesting and could be correctly understood in terms of the stress induced variation in the dielectric constant. The MC is observed to remain fairly constant between 10 to 500 kHz and possess a useful magnitude of M_c nearly 4%.