Enhances the Polishing Efficiency of Cerium-Based Abrasives on Sio2 Substrate by Increasing of Ce3+ Concentration on the Abrasive Surface

In this study, the effect of Ce3+ concentration on the polishing properties of Ce1-xLaxO2 abrasive (x = 0, 0.1, 0.2, 0.3) was investigated. The abrasives were characterized by XRD, SEM, TEM, Raman, and XPS. The polishing performance of abrasives was evaluated by AFM. All samples are CeO2 phase with cubic fluorite structure. And the particles were transformed from spherical into cubic with the increase of La3+. The oxygen vacancies are increased in CeO2 lattice by introducing the La3+, resulting in a significant improvement of Ce3+ concentration on the abrasive surface, but the Ce3+ concentration on the abrasive surface gradually became saturated when the x is 0.2 or more. The results of polishing performance proved that the polishing efficiency is closely related to the Ce3+ concentration generated by oxygen vacancies. The material removal rate (MRR) of raw CeO2 abrasives with a Ce3+ concentration of 7.57 % on SiO2 substrate was 39.31 nm/min, while the Ce0.8La0.2O2 abrasives with a Ce3+ concentration of 26.77 % was 66.56 nm/min, and the Ce0.7La0.3O2 abrasives with a Ce3+ concentration of 27.09 % was 68.96 nm/min. Furthermore, the differences in the removal rate of Ce3+ and Ce4+ in cerium-based abrasives on SiO2 substrate were also discussed