Preparation of mesoporous nanocrystalline tetragonal zirconia for catalytic methane combustion

Abstract

Mesoporous nanocrystalline tetragonal zirconia (ZrO₂) materials were synthesised via combining the soft templating method with the solid–liquid method. In brief, mesostructured zirconium hybrids were first prepared via the soft templating method and then ground with solid copper nitrate salts followed by low temperature heat treatment and further high temperature calcination in air. Finally, mesoporous nanocrystalline tetragonal ZrO₂ materials were obtained after etching in acid solution. The characterisation results indicate that the obtained mesoporous ZrO₂ materials have higher specific surface areas in the range of 100–300 m² g⁻¹ and pore diameters centred at 4·0–5·0 nm. The pore walls are composed of tetragonal ZrO₂ nanocrystalline particles with an average size of 1–15 nm. These mesoporous nanocrystalline tetragonal ZrO₂ materials as catalysts demonstrate good catalytic activity toward methane combustion, characterised by lower conversion temperatures (650–700°C) and active energies (75–90 kJ mol⁻¹) than those of the reported ZrO₂ materials, meaning their potential applications as catalysts or catalyst supporters in methane combustion.

Keywords:

• Mesoporous
• Zirconia
• Nanocrystalline
• Catalysis
• Methane combustion

Acknowledgements

The authors gratefully acknowledge the financial supports from the National Natural Science Foundation of China (grant no. 21206025) and the Natural Science Foundation of Hebei Province (grant no. B2013402008).