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Nanoparticles of neodymium orthophosphate(Nd PO4) were prepared through a facile wet co-precipitation technique. The X-ray diffraction(XRD) studies revealed the material belonging to monoclinic monazite phase with crystallite size of 30.8 nm. Scanning electron microscopic studies showed that the material was composed of a large number of agglomerated spherical particles having grain size of 92 nm. Thermogravimetric analysis suggested that the structural phase transition was seen above 800 °C. The spectroscopic investigations were carried out using Fourier transform infrared spectroscopy(FTIR). UV-VIS-NIR absorption spectrophotometer showed various transitions from the ground state 4I9/2 to various excited states within the 4f shell and the optical band gap came out to be 3.3 e V. The dielectric constant(ε′), dielectric loss(tan δ) and ac conductivity ln(σac) were measured in the frequency range of 5 k Hz to 1 MHz and in the temperature range of 40 to 500 °C. The dielectric measurement suggested that there was a shift in the value of transition temperature(Tc), thereby indicating relaxor behaviour of the material. The activation energy value decreased with increase in frequency, thereby suggesting the role of mixed ionic-polaronic conductivity.
Nanoparticles of neodymium orthophosphate (Nd PO4) were prepared through a facile wet co-precipitation technique. The X-ray diffraction (XRD) studies revealed the material belonging to monoclinic monazite phase with crystallite size of 30.8 nm. Scanning electron microscopic studies showed that the The material was composed of a large number of agglomerated spherical particles having grain size of 92 nm. Thermogravimetric analysis suggested that the structural phase transition was seen above 800 ° C. The spectroscopic investigations were carried out using Fourier transform infrared spectroscopy (FTIR). UV- VIS-NIR absorption spectrophotometer showed various transitions from the ground state 4I9 / 2 to various excited states within the 4f shell and the optical band gap came out to be 3.3 e V. The dielectric constant (ε ’), dielectric loss (tan δ) and ac conductivity ln (σac) were measured in the frequency range of 5 k Hz to 1 MHz and in the temperature range of 40 to 500 ° C. The dielectric measu rement suggested that there was a shift in the value of transition temperature (Tc), 而 向 indicating relaxor behavior of the material. The activation energy value decreased with increase in frequency, suggesting suggesting the role of mixed ionic-polaronic conductivity.