Efficient and Stable Gd₃Ga₅O₁₂:Cr³⁺ Phosphors for High‐Performance NIR LEDs

Abstract

Cr3+‐activated Gd3Ga5O12 garnet (GGG:Cr3+) near‐infrared (NIR) phosphors have shown promising applications in regulating plant growth. However, the low external quantum efficiency (EQE) results in a wall‐plug efficiency (WPE) of phosphor‐converted light‐emitting diodes (pc)‐LEDs of only ≈15%. Herein, an easy strategy to improve the luminescent properties of the GGG:Cr3+ phosphor is reported. Through optimization of the synthesized technology, the EQE is enhanced to 43.6%. Remarkably, the fabricated pc‐LEDs achieve a WPE as high as 34.3%. These results demonstrate a significant advancement in the development and applications of NIR phosphor materials and NIR pc‐LED devices.

Remote Control and Noninvasive Detection Enabled by a High-performance NIR pc-LED

“…Conversely, a smaller Δ E a weakens such intensity. The value of Δ E a can be calculated according to the Arrhenius equation: I t = I 0 1 + A exp true( − normalΔ E normala k normalB T true) Where I 0 and I t correspond to the integrated emission intensity of CLZSA:0.08Cr 3+ at the initial temperature and temperature T , A is a constant related to the host, k B denotes Boltzmann constant, and Δ E a signifies the activation energy. The value of Δ E a can be determined from the slope of the fitting line, as presented in Figure d, where the slope is approximately −0.26, indicating that the value of Δ E a of CLZSA:0.08Cr 3+ is 0.26 eV.…”

Enhanced quantum efficiency and thermal stability by crystal-field engineering in a Y(Ga,Al)3(BO3)4:Cr3+,Yb3+ phosphor for diverse short-wave infrared applications

“…The probability of TQ is closely related to the energy gap (Δ E ) between the lowest point of the excited state and the crossover point with the ground state. Δ E can be calculated using the following equation: 42 where I 0 , k , and A are constants, and I ( T ) represents the emission intensity at a given temperature T . In Fig.…”

Simultaneous NIR photoluminescence and mechanoluminescence from Cr3+ activated MgGa2O4 phosphors with multifunctions for optical sensing

“…The intensity of its emission spectrum relies on the crystal field environment of the host lattice. 19 Additionally, Cr 3+ ions possess notable light penetration properties. They can capture light signals passing through biological tissues, indicating potential for developing narrowband ML materials for the NIR I region.…”