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arXiv · 2101.05668

Heat capacities of nanostructured wurtzite and rock salt ZnO: challenges of ZnO nano-phase diagram

Konstantin V. Kamenev·Alexandre Courac·Petr S. Sokolov·Andrei N. Baranov·Felix Yu. Sharikov·Vladimir L. Solozhenko
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Abstract

Low-temperature heat capacities (Cp) of nanostructured rock salt (rs-ZnO) and wurtzite (w-ZnO) polymorphs of zinc oxide were measured in the 2-315 K temperature range. No significant influence of nanostructuring on Cp of w-ZnO has been observed. The measured Cp of rock salt ZnO is lower than that of wurtzite ZnO below 100 K and is higher above this temperature. Using available thermodynamic data, we established that the equilibrium pressure between nanocrystalline w-ZnO and rs-ZnO is close to 4.6 GPa at 300 K (half as much as the onset pressure of direct phase transformation) and slightly changes with temperature up to 1000 K.

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Konstantin V. Kamenev, Alexandre Courac, Petr S. Sokolov, Andrei N. Baranov, Felix Yu. Sharikov, Vladimir L. Solozhenko. 2021-01-14. Heat capacities of nanostructured wurtzite and rock salt ZnO: challenges of ZnO nano-phase diagram. https://doi.org/10.3390/solids2010007

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