The ferroelectricity of perovskite-type oxides with alkylamine interlayer

The ferroelectricity of layer perovskite-type oxides intermittent with alky lamine, synthesized by hydrothermal method, has been reported. Ferroelectri c hysteresis loops were observed in these newly synthesized powder crystals , which were pressed into wafers with platinum electrodes deposited by a pu lsed laser. Element analysis shows 69% cations between two layers were exch anged into alkyl ammonium. X-ray powder diffraction pattern, infrared spect ra, Raman spectra, and electron microscopy were used to characterize the sa mples. The results show that perovskite layer contributes to the ferroelect ric property. So-synthesized samples may make up a new group of materials w ith potential use especially in the field of fatigue-free ferroelectricity. (C) 1999 American Institute of Physics. [S0003-6951(99)00539-2].