Magnetoelectric (ME) Pb(Zr0.52Ti0.48)O3 (PZT)–NiFe2O4 bulk composites with various PZT volume fractions were prepared. The ME coupling coefficient, impedance, and flux density versus the frequency were measured. The magnetic bias and PZT volume fraction in the composites are investigated to optimize the ME output. It is revealed that ME resonances are caused by electromechanical resonance in the piezoelectric phase and magnetomechanical resonance in the magnetostrictive phase. Maximum magnetoelectric voltage coefficient resonance values of 6.7 V/cm Oe at 132.6 kHz and 6.12 V/cm Oe at 427.2 kHz for the composite with optimized PZT volume fraction of 0.55 were obtained at optimized magnetic bias of 0.6 kOe.

Perovskite oxide La 0.825 Sr 0.175 MnO 3 (LSMO) nanowires are synthesized using the anodized alumina oxide template technique and the characterization of the microstructure, magnetic and photoluminescence properties is performed. The as-prepared LSMO nanowires 50 nm in diameter and tens of microns in length exhibit polycrystalline perovskite structure. The magnetic measurement reveals the competition between antiferromagnetic ordering and spin glass state as ground state in the nanowires, which is different from the magnetic behaviours of bulk ceramic and single crystals. The photoluminescence (PL) spectroscopy demonstrates strong and broadband emissions with two luminescent peaks at 400 and 420 nm, respectively, which are believed to originate from the selftrapped excitons, oxygen vacancies and surface states, respectively. Nanoscale one-dimensional structures have attracted much interest because of their novel magnetic, electronic and optical properties as a result of their low dimensionality and quantum confinement effect. In addition to the well known examples of carbon nanotubes, ZnO nanobelts and so on, nanowires of complicated perovskite functional oxides such as ferroelectric BaTiO 3 and Pb(Zr, Ti)O 3 , as well as colossal magnetoresistance (CMR) manganites, have been synthesized [1][2][3][4][5]. Among the various methods used for fabrication of nanowires, the template synthesis method has been playing an important role in the fabrication of many kinds of nanowires and nanotubes for their interesting and useful features. Possible templates include nuclear track-etched polycarbonate membranes, nanochannel array glasses,

Water‐induced degradation of barium titanate (BTO) ceramics has been investigated using electrochemical hydrogen charging, in which the silver electrodes of BTO ceramic specimens are made cathodes in a 0.01M NaOH solution to evolve hydrogen by electrolysis of water. After 80 h of treatment, the resistance of BTO decreases by ∼3 orders of magnitude, and the dielectric loss obviously increases. The degradation can be explained by the reduction reaction of atomic hydrogen with BTO. Hydrogen acts as a donor in BTO, and electrons are formed by the reduction. It is proposed that the reduction reaction of atomic hydrogen at ambient temperature by electrolysis of water is an important origin for degradation of BTO‐based ceramic devices.

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