Advancements in Eu2O3-functionalized heterostructures: Synthetic pathways, performance mechanisms, and multi-functional sustainable applications

Rare earth metal oxide nanoparticles possess unique physicochemical properties that enable diverse technological applications. Among these, europium oxide (Eu 2 O 3 ), characterized by a wide band gap energy (~ 4.4 eV) and advantageous dielectric properties, has attracted significant research interest. This review comprehensively covers recent progress in the synthesis of Eu 2 O 3 and Eu 2 O 3 -functionalized heterostructures via diverse chemical routes, including precipitation, hydrothermal, solvothermal, sonochemical, sol-gel, and reflux methods. Particular emphasis is placed on the influence of key operational parameters, such as reaction temperature, time, and capping agents, on particle morphology and structural evolution. Furthermore, the functional performance and underlying mechanisms of these heterostructures across photocatalysis, luminescence, chemical sensing, and biological domain applications are critically evaluated, highlighting current challenges and prospects for sustainable utilization.