来源:TALANTA OPEN Volume11 DOI10.1016/j.talo.2025.100411
Zinc oxide (ZnO) serves as a highly adaptable semiconductor with a crucial role in various applications because of its crystal structure compatibility and significant band gap. Fabricating ZnO nanomaterials with tailored characteristics has become a prevalent and current focus. Within this framework, the integration of rare earth metals sparks interest due to their distinctive 4f electronic configuration, providing an exceptional opportunity to manipulate ZnO's optical, luminescent, and surface properties. This article examines the impact of rare earth metal doping on ZnO's structural and optical attributes, as well as the resulting improvements in various applications. We hope this review article offers comprehensive insights to guide the reasoned design and advancement of rare earth-doped ZnO (ZnO/RE) metals for various applications.
Rare earth element (REE) contains seventeen elements, fifteen lanthanide elements, scandium (Sc), and yttrium (Y) that show a similar chemical behavior. Lanthanide ions are notably stable due to the shielding effect of their outer, filled 5p² and 5p⁶ electron shells. Electronic transitions within the 4f orbitals of lanthanide ions can result in optical transitions spanning the entire solar spectrum. This distinct arrangement of electrons and separated energy levels characteristic of RE metals ion allows for the emission of ultraviolet (UV) or visible light when they absorb near-infrared photons. As doping, RE metals can become an impurity in the semiconductor's crystal lattice to obtain new properties.
Recently, RRE-doped semiconductors have been used in many applications due to the improvement of various properties –increasing the absorption range to visible decrease band gap energy and to prevent electron recombination. doping ZnO with RE metals introduces additional energy levels within its band structure, enabling p-type doping that serves as electron acceptors or n-type doping that functions as electron donors, which trap charge carriers and reduces the rate of recombination. Various RE metals have been employed as dopants to enhance the properties of ZnO.