Synthesis and characterization of translucent MgO-doped Al₂O₃ hollow spheres in millimeter-scale

Highlights: • Millimeter-scale Al₂O₃ hollow spheres are prepared by template synthesis method. • The mechanisms of Al₂O₃ hollow sphere formation are revealed. • The laser transmittance of Al₂O₃ hollow spheres are improved by MgO-doping. - Abstract: Translucent MgO-doped Al₂O₃ hollow spheres with millimeter-scale in diameter were prepared by a three-sintering-step method using polystyrene (PS) spheres as template through connection function of chitosan-assistant aggregation. The as-prepared hollow spheres were characterized by Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Field-Emission Scanning Electron Microscope (FE-SEM) and Electron Probe Microanalysis (EPMA). The results show that the obtained translucent MgO-doped Al₂O₃ hollow spheres has diameter of 1–2 mm, wall thickness of 130 μm and 532 nm pulse laser transmittance of 50%. It is also noted that the formation of PS–Al₂O₃ core–shell spheres is based on the connection function of –OH and –NH₂ groups in chitosan molecules. This method provides a synthesizing method for preparing translucent millimeter-scale hollow spheres which have a great potential application for Inertial Confined Fusion (ICF) required hollow pellet