A crystal defect led zero thermal quenching ß-NaYF4 : Eu3+,Dy3+ red emitting phosphor.

Red-light phosphors with extraordinary and stable thermal luminous properties must urgently be explored under the circumstances that commercial phosphors are suffering from serious thermal quenching effects and a lack of red-light components. Synthesized by a one-step hydrothermal method, a new type of NaYF4 : 0.065Eu3+,0.003Dy3+ phosphor with notable thermal luminous stability is reported in this study. As well as energy transfer between Dy3+ and Eu3+, this novel red-light phosphor manifests zero thermal quenching (ZTQ) performance under an increasing temperature of measurement. The ZTQ property stems from the interior defects of the crystal produced by the non-equivalence replacement between distinct ions. Density Functional Theory (DFT) calculations were utilized to verify the formation energy of two kinds of defects that make a vital contribution to the ZTQ performance of the NaYF4 : 0.065Eu3+,0.003Dy3+ phosphor. This finding could make some contributions towards research into improving thermal luminous properties and stability.

Crystal defect induced zero thermal quenching ß-NaYF4: Eu3+, Sm3+ red-emitting phosphor.

Red phosphors with brilliant performance are crucial for the application of white LEDs as their red-light component. However, the thermal quenching phenomenon is an inevitable obstacle in the practical application of various types of red-light phosphors. In this study, we report the preparation of a novel type of phosphor, NaYF4: 0.065Eu3+, 0.002Sm3+, possessing not only an energy transfer effect from Sm3+ to Eu3+ but also superior negative thermal quenching (NTQ) performance. The phosphor was synthesized via a one-step hydrothermal method, resulting in a prominent improvement in its luminous thermal stability supported by NTQ. The NTQ originated from the thermal stimulation excitement of the captured electrons in electronic traps, which is attributed to the non-equivalence between the different types of ions. The shape of the emission spectrum measured at high temperature was identical to that measured at room temperature, which not only showed the remarkable thermal stability of this novel type of phosphor but also the promising prospect of its practical application. This finding will contribute to improving the thermal stability of phosphor materials doped with lanthanide elements.