Effect of Zr doping on the high-temperature stability of SiO2 glass

A SiO2-ZrO2 glass was prepared by cold pressing and sintering, and the effect of ZrO2 on the high-temperature stability of SiO2 was studied. First-principle calculation based on density functional theory was applied to analyze the solution energies of Zr atom in ZrSiO4 and SiO2. The results show that Zr element can diffuse into SiO2 lattice, and influence the SiO2 structure in two ways, including introduction in the interstitial region and substituting a Si atom in SiO2. The interstitial Zr breaks the nearest SiAO bond to form ZrAO and ZrASi bonds, while the substitutional Zr has little influence on the SiO2 network. The interfacial adhesion energy between the Zr-doped SiO2 and the pure SiO2 increases from 3.93 J/m(2) to 4.56 J/m(2) with the introduction of Zr atom, which is beneficial for improving the high-temperature stability of SiO2 glass. (C) 2018 Elsevier B.V. All rights reserved.