Figure 4
(a) persistence time monitored at 1064 nm as a function of Ca concentration (x = 0.1, 0.3, 0.4 and 0.5). The inset shows the long persistent phosphorescence spectra of Z1-xCxGO (x = 0.1, 0.3, 0.4 and 0.5) samples and photoluminescence excitation spectrum monitored at 1064 nm of sample Z0.6C0.4GO. (b) Normalized photoluminescent and phosphorescent decay curves of Z0.6C0.4GO: 0.5%Cr/xNd (x = 0, 0.5%, 1% and 2%) samples. The monitored transition is Cr3+ [4T2 → 4A2]. (c) Thermoluminescence curves of Z1-xCxGO (x = 0.1, 0.3, 0.4, 0.5 and 0.7) phosphors measured 30 s after irradiation ceased. The inset shows the dependence of TL peak position as a function of Ca concentration. (d) XRD patterns for Z1-xCxGO (x = 0.1, 0.4, 0.5 and 0.7) phosphors. (e) EDX mapping of sample Z0.6C0.4GO. (f) 71Ga NMR spectra of Z1-xCxGO (x = 0, 0.2, 0.4 and 0.7) phosphors. (g) Normalized Raman spectra of ZGO-0.5Nd, ZGO-5Nd, CGO-0.5Nd, CGO-5Nd and Z1-xCxGO (x = 0.1, 0.4 and 0.7) phosphors.
