Mechanisms and dynamics of energy transfer sensitization in the Eu3+, Cr3+ and Fe3+ ions in the LiAl5O8 phosphors

• Published in: Optical materials 2022-06, Vol.128, p.112420, Article 112420
• Main Authors: Silva, Ariosvaldo J.S., Nascimento, Patresio A.M., da Carvalho, Iure S., Silveira, Wellisson S., Rezende, Marcos V. dos Santos
• Format: Article
• Language: English
• Subjects: Energy transfer; Lithium aluminates; Luminescence quenching; Solubility limit
• ISSN: 0925-3467; 1873-1252
• DOI: 10.1016/j.optmat.2022.112420

A mechanism of energy transfer sensitization in Eu-doped LiAl5O8 produced by the modified sol-gel method is proposed. The XRD results show the formation of the desired crystalline phase and the solubility limit of Eu dopant. Based in the PL results, a mechanisms of energy transfer (ET) and simultaneous excitation (SE) between the doping ion (Eu3+) and contaminating ions (Cr3+ and Fe3+) were elaborated based in the five possible dynamics. The first attributed to SE between Eu3+- Fe3+ characterized by direct excitation of Eu3+ and Fe3+ ions. The second is attributed to ET between Eu3+-Cr3+, attributed to the radiative transitions 5D0→7F1,2 and Cr3+ ion. Third mechanism is similar to the energy transfer described by the second mechanism in addition to Fe3+ sensitization. The fourth and fifth are due to the SE between Eu3+-Fe3+-Cr3+. •A mechanism of energy transfer sensitization in Eu-doped LiAl5O8is proposed.•Simultaneous excitation (SE) between the Eu3+and contaminating ions (Cr3+and Fe3+) were elaborated.•The effects of the Eu3+dopant concentration on the structural and optical properties also were investigated.