Cuboid-Size-Controlled Color-Tunable Eu-Doped Alkali–Lithosilicate Phosphors

Research on light-emitting diodes has considerably progressed over the years, so they are expected to possess excellent color rendition and high luminescent intensity. Cuboid-based red-nitride phosphors are highly promising because they are characterized by a narrow-band emission property, low energy waste, and excellent thermal stability. However, existing nitride phosphors have limited color diversity because of the lack of other anions. A new series of cuboid-based oxide phosphors called alkali lithosilicates is attracting considerable research attention because of these phosphors’ narrow-band emission and color-tunable properties. In this review, we demonstrate for the first time the features of nitride cuboid-based phosphors from a new perspective. The new perspective is then used to elucidate the color-control mechanism of the oxide cuboid-based phosphors. Finally, we propose a perspective about extending the color from the limit of current cuboid-based oxide phosphors. Our results can serve as a new reference for discovering new phosphors and controlling their luminescent color for practical applications.