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Laser‐driven phosphor‐converted white‐laser diodes are supposed to be next‐generation high‐brightness lighting sources for their unparalleled photoelectric efficiency and light quality, yet a significant obstacle hitherto has resided in the shortage and serious laser‐induced luminescence saturation of red emitters. Here, a hot‐pressing synthesis route to obtain high‐performance red‐emitting cordierite (Mg2Al4Si5O18:Eu2+) ceramic is developed, which enables the in situ formation of bulk specimens with high crystallinity (>90%) from the counterpart glass powders. A preeminent saturation threshold of 21 W mm−2 is realized in a red‐emitting Mg2Al4Si5O18:Eu2+ ceramic film converter. More importantly, the luminous exitance reaches 209 lm mm−2, which is 5 times that of commercial red phosphor‐converted‐LED, indicating breakthrough progress in the comprehensive light‐emitting performance of red converters. This work innovates the solid‐state synthesis of laser bulk converters from glass to meet the demanding requirements of advanced warm white laser lighting. [ABSTRACT FROM AUTHOR]

Near‐infrared (NIR) phosphor‐converted light‐emitting diodes (pc‐LEDs) lighting sources are applied in non‐destructive examination and illumination supplements for night monitoring. As a critical component of NIR pc‐LED, NIR phosphors are required to possess a high external quantum efficiency (EQE), super thermal stability, and broadband emission to meet applications. Here, Na2SrGe6O14:Cr3+ (NSGO:Cr) glass ceramics (GC) bulk via highly crystallization from glass precursor is fabricated and demonstrates an ultrabroad emission band centered at 815 nm with a full width at half‐maximum (FWHM) of 214 nm and a high EQE of 49.2%. Moreover, Yb3+ co‐doping significantly enhances Cr3+ → Yb3+ energy transfer (ET) due to the stronger Yb3+: 2F7/2‐2F5/2 absorption. Benefiting from the ET process, the Cr/Yb co‐doped GC exhibits NIR‐I/II emission with improved thermal stability from 30.1% to 65.0%. Furthermore, an encapsulant‐free NIR GC‐converted LED (GCc‐LED) is prepared and exhibits 52.2 mW NIR output power with a high photoelectric conversion efficiency (PCE) of 19.4%. Under a large current of 600 mA, the NIR device exhibits a watt‐level output power of 922.4 mW with a PCE of 9.1%. Compared to conventional NIR powder phosphors, NSGO:Cr/Yb GC with high performance can open up an avenue for the fabrication of high power NIR lighting sources. [ABSTRACT FROM AUTHOR]

Garnet-type Y 3 Sc 2 Ga 3 O 12 :Cr3+ phosphor has been synthesized by a solid-state reaction. XRD result revealed the successful phase formation and Cr3+ doping in Y 3 Sc 2 Ga 3 O 12. The excitation spectrum at about 260, 450, and 630 nm corresponded to three spin-allowed Cr3+ d - d intra-transitions of 4A 2 -4T 1 (4P), 4A 2 -4T 1 (4F), and 4A 2 -4T 2 (4F), respectively, among which the near infrared (NIR) emission peak at around 740 nm is identified. Moreover, the phosphorescence emission property, thermoluminescence and related luminescence mechanisms are discussed as well. The fabricated NIR phosphor-converted light-emitting diodes (pc-LEDs) suggest its potential of Y 3 Sc 2 Ga 3 O 12 :Cr3+ phosphor for non-visible light source application. • Garnet-type Y 3 Sc 2 Ga 3 O 12 :Cr3+ phosphor has been synthesized by solid-state reaction in air. • The Y 3 Sc 2 Ga 3 O 12 :Cr3+ phosphor exhibit both intense near infrared (NIR) and long persistent luminescence phenomenon. • The trap type and depth were also discussed according to thermoluminescence glow curves. • The possible fluorescence and long persistent luminescence mechanism in Y 3 Sc 2 Ga 3 O 12 :Cr3+ phosphors are analyzed. [ABSTRACT FROM AUTHOR]