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

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 Mg1-yGa2-xO4:xCr(3+),yNi(2+) 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.