Surface and grain boundary energies of tin dioxide at low and high temperatures and effects on densification behavior

• Published in: Journal of materials research Vol. 29; no. 9; pp. 1034 - 1046
• Main Authors: Chang, Chi-Hsiu, Castro, Ricardo H.R.
• Format: Journal Article
• Language: English
• Published: New York, USA Cambridge University Press 14.05.2014; Springer International Publishing; Springer Nature B.V
• Subjects: Acids; Adsorption; Analysis; Applied and Technical Physics; Atoms & subatomic particles; Biomaterials; Calorimetry; Contact angle; Energy; Grain boundaries; Heat; High temperature; Inorganic Chemistry; Materials Engineering; Materials research; Materials Science; Nanoparticles; Nanotechnology; Scanning electron microscopy; Sintering; Studies; Surface chemistry; Thermodynamics; Tin dioxide; Tin oxides
• ISSN: 0884-2914; 2044-5326
• DOI: 10.1557/jmr.2014.88

This work presents experimental data on the surface and grain boundary energies of tin dioxide nanoparticles at room temperature and high temperature conditions (quenched from 1300 °C), and a discussion of impacts on the fundamental understanding of the nondensification mechanism of SnO2 during sintering. The results were obtained using a combination of water adsorption microcalorimetry, high-temperature oxide melt drop solution calorimetry, and scanning electron transmission microscopy. At room temperature, the average surface and grain boundary energies of anhydrous SnO2 were 1.20 ± 0.02 and 0.71 ± 0.08 J m−2, respectively. At high temperature, SnO2 showed a surface energy of 0.94 ± 0.03 J m−2. This remarkable decrease was attributed to the lower oxygen pressure and was associated with a decrease in contact angle during sintering. This observation indicates a moderate but significant thermodynamic reason behind nondensification behavior of SnO2 in addition to common kinetic descriptions: high sintering temperatures and atmospheres cause smaller dihedral angles that decrease sintering stresses.