ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Structure-stability correlations in terms of microstructure during tin oxidation as examined by in situ high-temperature X-ray powder diffraction

Kohobhange S. P. Karunadasa

Materials Technology Section, Industrial Technology Institute, Colombo 7, Sri Lanka

E-mail: sujithkohobhange@yahoo.com

Received: 16 August 2023  Accepted: 17 January 2024

Abstract:

Structure-stability correlations in terms of microstructure related to tin oxidation were determined using an in situ high-temperature X-ray diffraction. Tin oxidation takes place over a broad temperature range between 300 and 900 °C, which resulted in SnO at 300 °C and SnO₂ that is thermodynamically more stable phase above 500 °C. The initial conversion from tin to SnO ultimately resulted in a matrix expansion by 36%, which is mainly due to unit cell volume contraction, resulting in a temporary decrease in tin lattice strain. The tin unit cell volume is rapidly increased during the initial heating, decreased slightly during the formation of SnO, and changed marginally during the oxidation to SnO₂.The tin lattice strain significantly increased from 0.84 × 10^–4 to 4.76 × 10^–4 and crystallite size decreased by 56% during the entire period of oxidation, indicating the ongoing lattice destabilization under thermal excitation. At high temperatures, SnO₂ is the most stable oxide form of tin, which is stabilized under the low lattice strain of 9.30 × 10^–5 and a large crystallite size of 39 nm that is mainly achieved via compact unit cell arrangement in space. The SnO has a strong orientation preference in the (112) direction, and as temperature increased, the orientation preference along this direction decreased. The stable SnO₂ exhibits a strong crystallite orientation preference along the (111) direction, which intensified with temperature, resulting in a preferred crystallite growth along this direction.

Graphical abstract

Keywords: Tin; Oxidation; Unit cell parameters; Microstructure; Structure-stability correlations

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-024-03333-5

Chemical Papers 78 (6) 3617–3628 (2024)