Fig. 9From: Near Infrared-Emitting Cr3+/Eu3+ Co-doped Zinc Gallogermanate Persistence Luminescent Nanoparticles for Cell ImagingExcitation and emission spectra of ZGGO:Cr3+,Eu3+ aqueous solution at room temperature. The inset shows the digital photos of ZGGO:Cr3+,Eu3+ aqueous solution under irradiation of 254 nm UV lightBack to article page