Selective Cation Exchange Enabled Growth of Lanthanide Core/Shell Nanoparticles with Dissimilar Structure

Area of Science:

• Materials Science
• Nanotechnology
• Chemistry

Background:

• Core/shell nanostructures are crucial for advanced functionalities but are typically limited to isomorphic structures.
• Lanthanide-based nanomaterials are vital for photon conversion applications.

Purpose of the Study:

• To develop a method for creating lanthanide core/shell nanoparticles with dissimilar core and shell structures.
• To improve the performance of photon conversion materials through novel nanostructure engineering.

Main Methods:

• A selective cation exchange strategy was employed to construct heterostructured nanoparticles.
• Hexagonal NaLnF4 (lanthanide) cores were coated with cubic CaF2 shells.
• Surface structure evolution from hexagonal to cubic was induced via cation exchange.

Main Results:

• The heterostructured CaF2 shell significantly enhanced upconversion emission, increasing absolute quantum yield from 0.2% to 3.7%.
• The novel structure effectively suppressed interfacial diffusion and leakage of lanthanide ions (Ln3+).

Conclusions:

• This work presents a new approach for fabricating heterostructured core/shell nanoparticles with non-isomorphic components.
• The findings provide valuable insights for tuning nanoparticle properties and enhancing their performance in applications like photon conversion.