Synthesis, morphology and optical properties of pure and Eu3+ doped β-Ga2O3 hollow nanostructures by hydrothermal method

Pure and Eu3+ doped β-Ga2O3 hollow nanostructures were synthesized by hydrothermal and calcination processes using carbon spheres as templates in ethanol-water solution. Field-emission scanning electron microscopy and high-resolution transmission electron microscopy analysis revealed β-Ga2O3 hollow nanostructures with diameters of approximately 200 nm and shell thickness of about 20 nm. The X-ray diffraction analysis revealed that the carbon@Ga(OH)CO3 core-shell nanostructures were in amorphous phase before calcination. After calcination, the amorphous core-shell structures yielded highly crystalline β-Ga2O3 hollow nanostructures with spherical shape. The presence of the Ga(OH)CO3 in the shell components is confirmed by the Fourier transform infrared spectrum. The Eu3+ doped β-Ga2O3 hollow nanostructures showed strong red emission corresponding to the 5D4 → 7FJ transition.