A Method for Quantitative Phase Analysis of Nanocrystalline Zirconium Dioxide Polymorphs

Area of Science:

• Materials Science
• Crystallography
• Analytical Chemistry

Background:

• Accurate quantitative phase analysis of nanocrystalline materials is crucial for understanding their properties.
• Zirconium dioxide (ZrO2) exhibits multiple polymorphs (tetragonal, monoclinic, cubic) with distinct characteristics.
• Existing methods for analyzing ZrO2 mixtures can be limited in accuracy and scope.

Purpose of the Study:

• To develop a reliable method for quantitative phase analysis of nanocrystalline zirconium dioxide polymorphs using X-ray diffractometry.
• To derive and validate formulas for determining the weight ratios of different ZrO2 phases.
• To assess the impact of cubic ZrO2 on the analysis and its potential to be grouped with the tetragonal phase.

Main Methods:

• Development of a quantitative phase analysis method based on X-ray diffractometry (XRD).
• Derivation of theoretical formulas and their verification through rigorous calculations and experiments.
• Implementation of an iterative process to enable experimental verification without pure polymorph standards.
• Investigation of the influence of cubic ZrO2 on XRD patterns of mixtures with tetragonal ZrO2.

Main Results:

• A novel XRD-based method accurately determines the weight ratios of tetragonal ZrO2 (t-ZrO2) and monoclinic ZrO2 (m-ZrO2) in nanocrystalline mixtures.
• Theoretical calculations and experimental results show high agreement, validating the method's reliability.
• Mutual substitution between t-ZrO2 and cubic ZrO2 (c-ZrO2) has minimal impact on XRD patterns, allowing them to be treated as a single phase.

Conclusions:

• The developed XRD method provides a valid and reliable approach for quantitative phase analysis of nanocrystalline ZrO2 polymorphs.
• The findings demonstrate that t-ZrO2 and c-ZrO2 can be considered a combined phase for analysis purposes.
• This method shows potential for adaptation and application to other material systems requiring quantitative phase analysis.