Magnetic and low-field magnetoelectric properties of 2.5 %Sm:PMN-PT–(Ni0.8Zn0.2)0.6Co0.4Fe2O4 multiferroics

Multiferroic materials are capable for achieving mutual coupling between multiple physical fields, including mechanics, electronics and magnetism. However, materials with high magnetoelectric output under low magnetic fields are of great significance in practical applications, which is the dominate purpose of this study. Herein, 2.5 %Sm:PMN-PT–(Ni 0.8 Zn 0.2 ) 0.6 Co 0.4 Fe 2 O 4 multiferroics had been prepared by solid-state method. For 0–3 types, the X-ray diffraction results demonstrate the presence of perovskite and spinel phases, yet the pyrochlore phase emerges when the molar ratio of ferrite is relatively high, which is ascribed to the reduction of the Pb 2+ concentration in the sintering atmosphere. Due to ionic diffusion and small strains between the two ferro-phases, the diffraction angle of the spinel phase varies accordingly. Scanning electron microscope images indicate the interlaced distribution of the two ferro-phase grains. Many magnetic parameters increase with ferrite molar ratio increasing, e.g., saturation magnetization ( M s ), coercivity, remanent magnetization, theoretical saturation magnetization ( M s -the ), and magnetocrystalline anisotropy constant, etc. The observed increase in M s /M s -the with ferrite molar ratio is attributed to the attenuated hindering of magnetization caused by the nonmagnetic ferroelectric grains. The ferroelectric grains can absorb microscopic strain and hinder the magnetic domains rotation, which reduce the magnetostrictive strain and sensitivity, and meanwhile increase the magnetic field required to reach the maximum strain sensitivity, respectively. For 2-2 tri-layer types, the magnetoelectric coefficient reaches 13.21 [mV/(cm·Oe)] at a low DC magnetic field of 200 Oe when the AC magnetic field of 10 mOe at 1 kHz, indicating its abilities for current-to-voltage conversion applications. This work investigates the diverse physical properties of an facile PMN-PT–CoFe 2 O 4 -based ceramic composite, and demonstrates its potential application in magnetic-to-electrical energy conversion.