A novel highly thermal-stable Ca2GaNbO6: Sm3+ phosphor with excellent color purity for high CRI wLEDs and security ink

In this study, a Sm3+ ion-doped double perovskite structure oxide was developed to obtain a novel Ca2GaNbO6: Sm3+ orange-red phosphor, which has compensated for the lack of a red component in commercial wLEDs. The results of morphological features and phase structure have confirmed that the synthesized compound maintains the same structure as Ca2GaNbO6, and that Sm3+ successfully enters into the main lattice of Ca2GaNbO6. In terms of optical properties, the photoluminescence (PL) emission spectra monitored at 406 nm has the strongest emission peak at 599 nm and shows strong orange-red light. The spectral shapes of PL at different concentrations remain consistent without wavelength drift, and perform best when the concentration is 3 mol%, that is, the concentration quenching point is 3 mol%. The quenching phenomenon is believed to be mainly attributed to dipole-dipole (d-d) interaction. The Ca2GaNbO6: 0.03Sm3+ phosphor shows excellent color purity (CP = 99.0%) and low color temperature (CCT = 1664 K) in terms of chromaticity (CIE). In terms of heat resistance, the thermal stability of Ca2GaNbO6: 0.03Sm3+ phosphor is 82.80% (423 K). The internal quantum efficiency (IQE) is 34.4%. In terms of applications, the wLEDs made of Ca2GaNbO6: 0.03Sm3+ phosphor emits warm white light and exhibit excellent performance in color rendering index and correlated color temperature (CRI = 94.5, CCT = 3877 K). At the same time, Ca2GaNbO6: Sm3+ phosphor shows good solubility in PVA. Research shows that Ca2GaNbO6: Sm3+ phosphor has good performance in the fields of wLEDs and security ink.