Highly stable and efficient pure green up-conversion emission of rod-like β-NaGdF4:Yb3+,Ho3+ submicro-crystals via ion-exchange for fluorescent labeling

Herein, we report the highly stable and efficient pure green up-conversion emission of β-NaGdF₄:Yb³⁺,Ho³⁺ rod-like submicro-crystals, synthesized via an ion-exchange method. This material shows great potential for fluorescence labeling applications.