Green synthesis strategy to construct strong zero-phonon line red emission phosphor Na2SiF6:Mn4+: Photoluminescence properties, thermal stability and application in warm white LEDs

Advancing Red-Emitting Fluoride Phosphors for Highly Stable White Light-Emitting Diodes: Crystal Reconstruction and Covalence Enhancement Strategy

“…White light-emitting diodes (WLEDs) find wide applications in solid-state lighting, liquid crystal display backlighting, and more. − The properties of red phosphors play a crucial role in determining the technical indicators of WLED devices, such as luminous efficacy (LE), color rendering index (CRI), color gamut, and overall stability. − However, several existing red-light material options present limitations in terms of light efficiency, stability, and complexity of preparation. Eu 2+ -doped nitrides, despite their wide red emission, suffer from a significant portion of the spectrum falling beyond the sensitivity range of the human eye, resulting in reduced light efficiency. , Red quantum dots like InP, CdSe, and perovskites exhibit poor stability and involve intricate preparation processes. − Eu 3+ /Mn 4+ -activated oxides, on the other hand, are challenging to excite with blue light. − In contrast, Mn 4+ -doped fluorides demonstrate effective excitation by blue light, possess a narrow emission spectrum (∼630 nm, aligning with the B.T.2020 display standard), high quantum efficiency (QE), and excellent thermal stability, making them a subject of widespread attention. , …”

Theoretical calculations and photoluminescence properties of Sr4Al14O25:Mn4+ red phosphors doped with Li+

“…Fluorides (such as K 2 SiF 6 :Mn 4+ , Rb 2 KScF 6 :Mn 4+ , Na 2 SiF 6 :Mn 4+ and Na 3 Li 3 In 2 F 12 :Mn 4+ ) are usually synthesized using wet chemical methods. 20,21 Mn 4+ prefers to replace the position of A (Al, Sc, Si, In, etc.) in the [AO 6 ] octahedron to form the [MnO 6 ] luminescence center, resulting in red light emission in the range of 620-750 nm.…”

Green Synthesis and Luminescent Properties of Mn<sup>4+</sup> Doped Red Phosphor for WLED

“…Compared with traditional incandescent lamp and fluorescent lamp, white light emitting diode (WLED) has the advantages of low heat, low power consumption, fast response, long life and so on [1] [2]. However, for the traditional WLED device with yellow Y 3 Al5O 12 :Ce 3+ (YAG: Ce) phosphor excited by blue InGaN chip, due to the lack of red light components, there are problems of high correlation color temperature(CCT, CCT > 4500 K) and low color rendering index (CRI, Ra < 80) [3]. Mn 4+ activated phosphors have been reported for a variety of fluoride and oxide substrates [4] [5] [6] [7] [8].…”