Mini Light‐Emitting Diode Technology with High Quantum Efficient NIR‐II Partially Inverse Spinel MgGa₂O₄:Cr³⁺,Ni²⁺ Nanophosphors

Abstract The increasing demand for second near‐infrared (NIR‐II) region materials, which retain the advantage of minimal scattering and immense applications in the medical and NIR spectroscopy field, has led to considerable research in this region. A mini light‐emitting diode (mini‐LED) is essential for backlighting liquid crystal displays, indicating the need for the small size of phosphors. However, current market phosphors must be more significant to be a viable option for mini‐LEDs. This scenario necessitates the synthesis of small‐sized phosphors to be used in mini‐LEDs. In this work, a mesoporous silica nanoparticle (MSN) and incorporated the Mg_1−yGa_2−xO₄:xCr³⁺,yNi²⁺ system is fabricated. The structural investigation confirmed the single phase of MgGa₂O₄ with a pore size of 2.73 nm for the MSN. The results showed a steady NIR‐II signal at 1270 nm and an enhanced energy transfer with a high quantum yield of 79.2% for a nanophosphor. The mini‐LED package revealed a 1000–1600 nm signal, qualifying the nanophosphor for realistic applications. This work can make provisions for various NIR‐II nanophosphors in the LED industry.