Abstract
Multiferroic YMnO3 nanoparticles with a narrow size distribution and high specific surface area (304 m(2)g(-1)) were synthesized using a low temperature polymeric citrate precursor route for the first time. The crystal structure of the monophasic hexagonal YMnO3 nanoparticles was estimated by powder X-ray diffraction studies. The transmission and scanning electron microscopic studies revealed nearly hexagonal nanostructures with an average grain size of similar to 48 nm. The optical band gap was found to be 3.7 eV and photoluminescence studies also suggest the wide band gap semiconducting nature of YMnO3. DC-magnetization studies of YMnO3 nanoparticles show ferromagnetic hysteresis with saturation magnetization of 21.19 emu g(-1). The appearance of a room temperature ferroelectric loop at 50 kHz has been observed for the first time with an improved remanent polarization of 0.0084 mu C cm(-2). The dielectric properties on sintered disks were also investigated as a function of frequency and temperature.