Structural and dielectric studies of lanthanum-doped barium neodymium titanate

ABSTRACTThe high quality factor, high dielectric constant, low dielectric loss and small temperature coefficient of resonant frequency are the most desirable characteristics of the microwave dielectric materials. Considering the hazardous nature of lead-based ceramics, many research groups have paid great attention to the research on non-lead-based perovskite ceramic. Here, we synthesize the material BaNd2-xLaxTi4O12 (for x = 0.02, 0.04, 0.06 and 0.08) by choosing the method which is of low cost and easy. The X-ray diffraction (XRD) data confirm its orthorhombic crystal structure and the scanning electron microscopy (SEM) picture shows a grain size of less than 2 µm. The dielectric measurement gives temperature independency in the range from room temperature to 523 K, which is observed to be independent of level of concentration. The complex impedance measurement shows a double hemisphere indicating separate grain and grain-boundary contributions and is well resolved at higher temperature.