Study on the electronic structure and mechanical stability of three TiO2/CeO2 interfaces for high-quality and efficient polishing of core-shell abrasive

Abstract

Due to the problems of easy agglomeration and high polishing defect rate of the single CeO2 particle, this study constructed a core-shell structured TiO2/CeO2 composite abrasive with the aim of achieving high-quality and efficient polishing. In this study, the core-shell TiO2/CeO2 composite abrasive was constructed to achieve high-quality and efficient polishing. The atomic structure, electronic structure, and mechanical property of a-TiO2(001)/CeO2(001), a-TiO2(101)/CeO2(111) and r-TiO2(110)/CeO2(111) interfaces and their interfaces containing O vacancy were studied using first principles calculations. The results indicated that the structure stability of three TiO2/CeO2 interfaces was determined by the number and length of Ti-O and Ce-O covalent bonds generated in the interface region. The adhesion work of the stable a-TiO2(001)/CeO2(001) interface and the most unstable r-TiO2(110)/CeO2(111) interface were 2.28 and 0.53 J/m2, respectively. Oxygen vacancy defects reduced the adhesion work and ideal shear strength of three TiO2/CeO1.94 interfaces. The fracture of Ti-O bonds in the interface region was the reason for the failure of the a-TiO2(001)/CeO2(001) and a-TiO2(101)/CeO1.94(111) interfaces, while the failure of other interfaces was mainly caused by the fracture of Ce-O bonds in the interface region. Under shear strain, the chemical activities of the r-TiO2(110)/CeO2(111) and r-TiO2(110)/CeO1.94(111) interfaces were reduced.