Non-equilibrium crystallization pathways of manganese oxides in aqueous solution

Area of Science:

• Materials Science
• Chemistry
• Nanotechnology

Background:

• Aqueous precipitation of transition metal oxides often forms unpredictable non-equilibrium phases.
• Traditional phase diagrams do not account for metastable phases, complicating targeted synthesis.

Purpose of the Study:

• To develop a theoretical framework for understanding nanoscale and metastable energy landscapes of Pourbaix (E-pH) diagrams.
• To provide quantitative insights into the size-dependent thermodynamics of metastable oxide nucleation and growth.

Main Methods:

• Combining a novel theoretical framework with classical nucleation theory.
• Interrogating multistage oxidation pathways of manganese oxides under varying solution conditions.

Main Results:

• Demonstrated that subtle variations in pH and redox potential can alter non-equilibrium crystallization pathways.
• Calculated the influence of solution conditions on metastable intermediate formation.

Conclusions:

• The developed framework offers a predictive platform for navigating thermodynamic and kinetic landscapes.
• Enables the rational synthesis of target metal oxide materials by controlling metastable phase formation.