Sensitization Mechanism of Alumina Aerogels: Introducing Gd³⁺ as a Sensitizing Ion to Enhance the Luminescence Intensity of Tb³⁺

To enhance the luminous intensity of phosphors containing Tb 3+ , Gd 3+ was used as a sensitizing ion to recombine with Tb 3+ . Gd 3+ and Tb 3+ ions were loaded on the Al 2 O 3 aerogel matrix with nano porous structure via a simple and facile sol‐gel method. After vacuum drying and calcination, Al 2 O 3 : Tb 3+ , Gd 3+ composite aerogel materials were obtained. Al 2 O 3 aerogel matrix has three‐dimensional nanostructure and good chemical stability, which can provide stable crystal field and emission site for the rare earth activated ions. The results indicated that the introduction of Gd 3+ can effectively enhance the luminescence intensity of Al 2 O 3 : Tb 3+ at 543 nm under 260 nm UV excitation. The optimal ratio of Gd 3+ and Tb 3+ was determined to be 1: 1. The mechanism of Gd 3+ sensitization to Tb 3+ can be considered as electric multipole resonance transmission. We expected that this work could provide guidance for the development of enhancing the luminous intensity of green phosphors for lamp.