Design of a Novel La₃Si₆N₁₁:Ce³⁺ Phosphor-in-Glass Film for High Power Laser Lighting: Luminous Efficiency toward 200 lmW^–1

Abstract

Inorganic fluorescent glass films have been widely considered in the field of high power laser lighting because of their excellent comprehensive properties as fluorescent conversion materials. Herein, we adjust the optimum sintering temperature to prepare a series of La 3 Si 6 N 11 :Ce 3+ phosphor-in-glass films (LSN PiFs) with excellent optical properties on a single sapphire structure. The prepared LSN PiF has ultrahigh internal quantum efficiency (IQE) (98%) and excellent thermal stability. The thermal conductivity at room temperature can reach 9.8 Wm −1 K −1 . When the temperature is 100 °C, the fluorescence intensity can still be maintained. The LSN:Ce phosphor particles did not react with the glass matrix and retained the original luminescence properties. Moreover, by further adjusting the concentration and thickness of LSN PiF, the luminous flux and luminous efficiency of LSN PiF under optimal conditions can reach 1071.73 and 207.58 lmW −1 under the excitation of 460 nm, which is the optimal result reported so far. In addition, the color rendering index (CRI) and low color temperature (CCT) are 64.05 and 5612.6 K, respectively, and the color coordinates are all close to the white light region. All the results show that LSN PiF has great application prospects in the high quality and high brightness laser lighting field.

Double Perovskite Single Crystals with High Laser Irradiation Stability for Solid-State Laser Lighting and Anti-counterfeiting

“…Limited by the power of our laser device, 12.41 kW/cm 2 is the highest power density output that can be realized. This value is much higher than the laser-damaged threshold of conventional Y 3 Al 3.5 Ga 1.5 O 12 : Ce 3+ phosphor (3.90 kW/cm 2 ), AlN-YAG: Ce 3+ phosphor (3.96 kW/cm 2 ), AlN-CaAlSiN 3 : Eu 2+ phosphor (10.37 kW/cm 2 ), etc., as summarized in Figure h. − …”

Rational Design of Nitride Phosphor-In-Glass with Robust Stability and Photoluminescence Performance

“…The results show that the glass (∼2.15), which has a refractive index similar to that of the phosphor (∼2. 19), has lower reflectivity and higher quantum efficiency at the interface between phosphor powder and glass. DSC curves of telluride glasses determined the glass-transition temperature (T g = 413 °C) and onset of crystallization temperature (T x = 539 °C).…”

“…30 Li et al used La 3 Si 6 N 11 :Ce 3+ nitride phosphor combined with borosilicate glass at a temperature of 1000− 1090 °C. 19 All of the aforementioned studies utilized borosilicate glass as the matrix. However, the high cosintering temperature can cause an interface reaction between glass and phosphor.…”

“…In the realm of solid-state lighting, white light-emitting diodes (WLEDs) hold immense promise owing to their energy efficiency and environmentally benign attributes, favorable luminous efficacy, as well as their uncomplicated and easily fabricable structures. − These light sources find applications in diverse fields, such as plant growth illumination, signaling and indicator lamps, and flat-panel displays. − Nevertheless, conventional organic phosphor resin converters suffer from obvious drawbacks, including inadequate thermal stability, low thermal conductivity, and susceptibility to aging-induced degradation and phosphor corrosion. These issues collectively lead to reduced efficiency of white light emission from the WLEDs and shortened operational lifespan of the devices. − …”

“…Xiang et al selected borosilicate glass in combination with nitride red phosphor, utilizing a cosintering temperature range of 750–850 °C . Li et al used La 3 Si 6 N 11 :Ce 3+ nitride phosphor combined with borosilicate glass at a temperature of 1000–1090 °C . All of the aforementioned studies utilized borosilicate glass as the matrix.…”