AbstractCr3+‐doped near‐infrared (NIR) phosphors have attracted significant attention in recent years. Despite this, achieving high‐performance NIR phosphors with broadband emission and excellent thermal stability remains a considerable challenge. This study presents Lu3Ga5O12:Cr3+, which demonstrates a tunable emission peak ranging from 705 to 759 nm and an increased full‐width at half‐peak maximum (FWHM) from 46 to 139 nm by substituting the [Mg2+‐Ge4+] chemical unit for the [Ga3+‐Ga3+] unit. Additionally, in Lu3MgGa3GeO12:Cr3+, Yb3+, an energy transfer channel (Cr3+‐Yb3+) is constructed. Under blue light excitation, the characteristic emission peaks of Cr3+ (600–900 nm) and Yb3+ (900–1100 nm) are observed simultaneously. However, the emission band between 850 and 900 nm is relatively weak, resulting in a discontinuous emission spectrum. To address this, Lu3MgGa3GeO12:Cr3+, Yb3+, Nd3+ phosphors are proposed, which exhibit a continuous broadband NIR emission with a FWHM of 253 nm and internal quantum efficiency of 47.3%. The luminescence intensity retains 81% of its room temperature value even at 423 K. Combining this new phosphor with a blue LED chip results in a portable NIR light source with potential applications in non‐destructive detection, information encryption, bio‐imaging, and NIR remote control. This work offers a novel perspective for developing high‐performance NIR phosphors.
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