Details

Autor(en) / Beteiligte

• Castaing, Victor
• Sontakke, Atul D
• Xu, Jian
• Fernández-Carrión, Alberto
• Genevois, Cécile
• Tanabe, Setsuhisa
• Allix, Mathieu
• Viana, Bruno

Titel

Persistent energy transfer in ZGO:Cr,Yb: a new strategy to design nano glass-ceramics featuring deep red and near infrared persistent luminescence

Ist Teil von

• Physical chemistry chemical physics : PCCP, 2019-09, Vol.21 (35), p.19458-19468

Erscheinungsjahr

2019

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• ZnGa 2 O 4 :Cr 3+ , owing to its persistent luminescence properties in the deep red range, is an exceptional material in view of foreseen in vivo imaging applications. In the present work, we report the elaboration process and detailed investigations of the optical properties of nano glass-ceramics composed of spinel ZnGa 2 O 4 :Cr 3+ ,Yb 3+ nanocrystals embedded in a transparent, silica rich, glass matrix. The as-prepared materials show good incorporation of the dopants in the crystallites leading in both Cr 3+ and Yb 3+ emissions. These emissions occur while exciting in the Cr 3+ bands, indicating an energy transfer process from Cr 3+ to Yb 3+ . Furthermore, excitation in the Yb 3+ band in the near-infrared (NIR) range suggests an interesting up-conversion process, which promotes the Cr 3+ emission. Persistent luminescence of both Cr 3+ and Yb 3+ doping ions can be activated by charging the Cr 3+ excitation bands, leading to persistent luminescence of zinc gallate nanocrystals in both first and second biological windows. The influence of Yb 3+ co-doping on persistent luminescence properties has been investigated by persistent luminescence decay profiles and thermoluminescence studies. Indeed, thermoluminescence glow curves of Yb 3+ exhibit similar shape to those of Cr 3+ but appear broader and shifted towards higher temperatures. This temperature shift may be explained by the temperature dependence of the involved energy transfer process. ZnGa 2 O 4 :Cr 3+ ,Yb 3+ nanocrystals, elaborated via glass crystallisation, show strong deep red and near infrared persistent luminescence chargeable by red light.