The structural transition of Gd2O3 nanoparticles induced by high pressure

The structural transition of nanosize Gd2O3 is studied using high pressure energy dispersive x-ray diffraction and high pressure photoluminescence. The original structure of the nanosized sample shows a mixture of cubic and monoclinic structure. Our results show that the cubic and most of the monoclinic structure turns into hexagonal structure above 10.35 GPa. But a small proportion of monoclinic structure can be present up to the highest pressure, 36.2 GPa. When the pressure is released, the hexagonal structure partly reverts to monoclinic structure, so the sample shows a mixture of hexagonal and monoclinic structure. The structural transition from monoclinic to hexagonal structure is reversible.