Oriented attachment (OA) mediated characteristic growth of Gd2O3 nanorods from nanoparticle seeds

Herein, we demonstrated the oriented attachment (OA) driven formation and characterization of Gd2O3 nanorods. The nanorods were synthesized via a surfactant free, inexpensive hydrothermal route and considering similar to 30 nm nanoparticles as the seed. While maintaining a cubic phase throughout the process, complete transformation of Gd2O3 nanoparticles to nanorods was found to occur at an elevated temperature (similar to 180 degrees C) of the hydrothermal reaction. The elongated Gd2O3 nanostructures, as revealed from transmission electron microscopic imaging, possessed an average diameter of similar to 33 nm and an approximate length of 172 nm. From the kinetics of OA process, the activation energy of formation was estimated to be similar to 25 kJ/mole. The existence of defect mediated radiative emission was ascertained from the asymmetric broadening of luminescence spectra. The defect emission arising from the Gd2O3 nanorods was nearly 1.4 times stronger than that of nanoparticles. The morphological evolution and growth kinetics were discussed along with the luminescence and electron paramagnetic resonance features.