Particulate composites of Li0.5Co0.75Fe2O4 and BaTiO3 with mixed structure have been synthesized by the normal ceramic method with a variation of the molar percentages. X-ray diffraction was used to carry out the structural analysis and confirm the presence of constituent phases in the composites. The dc resistivity was measured as a function of temperature and molar percentage of constituent phases. The relative dielectric constant with variation of frequency (in the range 20 Hz to 1 MHz) and temperature at four fixed frequencies (i.e. 1 kHz, 10 kHz, 100 kHz and 1 MHz) was studied. The ac conductivity was calculated from dielectric data to understand the conduction mechanism. Hysteresis measurements were carried out to determine the saturation magnetization. The variation in magnetic behaviour with the composition of constituent phases was measured as a function of the applied dc magnetic field. A maximum magnetoelectric voltage coefficient of about 372 µV cm−1 Oe−1 was observed for the (0.3)Li0.5Co0.75Fe2O4/(0.7)BaTiO3 composite. The ME conversion factor has been explained in terms of molar constitution of ferrite–ferroelectric phases and resistivity.

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Dielectric materials developed from Tantalum (Ta) doped AgNbO3 (ATN) show excellent properties in variety of electronic technologies. In the temperature range of 70 to 400 °C, four major dielectric abnormalities were observed in ATN (x = 0.1) while in ATN (x = 0.2) the maxima of M1-M2 phase shift to low temperature value. ATN ceramics’ dielectric properties dominate temperature and electric field-based performance, which has a major effect on their properties. This study looked into the dielectric properties in ATN.

The electrical properties of the titanium doped AgNbO3 system are defined in this paper. In the modified system, doping moderately replaced Nb5+ with Ti4+ ion where the ceramics are prepared using solid-state reaction technique. The dielectric characteristics were examined at frequencies ranging from 1 kHz to 100 kHz. The dielectric value of the modified systems increased substantially while the P-E curve emerged with a value of relatively increased spontaneous polarization.

Every year, millions of people incur damage to sensory receptors that interact with the external environment. Two areas of concern are hearing loss (affecting around 430 million) and burns (affecting 11 million annually). Current treatments for burns involve skin grafts, which are expensive and prone to rejection by the body. Current treatments for hearing loss involve implants and hearing aids, which have limited sensitivity, need batteries and charging, are expensive, and are prone to infection. Thus, there is a need for a self-powered, flexible, biocompatible, antibacterial, and inexpensive solution that can respond to stimuli at a rate comparable to tissue. Piezoelectric materials convert mechanical energy into electricity, thus replicating touch and hearing by simulating nerve signals. In this study, piezoelectric membranes with varying ratios of polyvinylidene fluoride (PVDF) and zinc oxide (ZnO) were fabricated using electrospinning. These membranes were characterized with scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), stress-strain analysis, and piezoresponse testing. Results showed that increasing the amount of PVDF made the membrane more flexible but reduced its piezoelectric potential (decrease in PVDF β-phase). Increasing the amount of ZnO significantly increased piezoelectric potential (increase in PVDF β-phase) but degraded the flexibility and usability of the membrane. Therefore, a 1:1 w/w ratio of PVDF to ZnO is the optimum ratio for balancing both piezoelectric potential and flexibility. These results support the hypothesis that composites of PVDF and ZnO can help realize self-powered hearing rehab devices and wearable electronic skin.