Metal Oxides of Group 4: General Insights and the Synthesis of ZrO2/HfO2 and ZrO2:Eu/ZrO2 Core/Shell Nanocrystals

Abstract

Metal oxide nanocrystals, like ZrO₂ and HfO₂, serve as hosts for optically active lanthanide ions. However, synthesizing colloidally stable nanocrystals with complex architectures remains challenging. We have pioneered the synthesis of metal oxide core/shell nanocrystals, where HfO₂ epitaxially grows onto ZrO₂. The beneficial effect of the shell on the optical properties is demonstrated by investigating the photoluminescence of ZrO₂:Eu and of ZrO₂:Eu/ZrO₂ after growing a protective zirconia shell on it.^[1]