Paramagnetic Ho2O3 nanowires, nano-square sheets, and nanoplates

The morphology control of holmium oxide (Ho2O3) nanostructures has rarely been reported. In the present study, uniform Ho2O3 nanowires, nano-square sheets, and nanoplates were synthesized via the hydrothermal method and were characterized using scanning electron microscopy, high-resolution transmission electron microscopy, Fourier-transform infrared spectroscopy, thermogravimetric analysis, ultraviolet-visible-near-infrared absorption, and X-ray photoelectron spectroscopy. The morphology was observed to be composed of different crystal phases and Ho complexes, but it changed to the same cubic Ho2O3 crystal phase upon high-temperature thermal treatment. Paramagnetic properties were obtained and discussed for the three different morphologies mentioned above. The newly reported morphologies and the physicochemical properties reported herein will widen the application scope of Ho oxide materials.