Designing high-efficiency red-emitting Mg2In1-zSczSbO6:Mn4+,Li+ phosphors for plant growth lighting

In this work, a synergistic strategy of small cation substitution and charge compensation to realize efficient red luminescence has been developed, which greatly improves the luminescence performance of Mg2InSbO6:Mn4+ by modulating the degree of distortion of the Mn4+ lattice site. The doping Mn ion is stabilized in the tetravalent state and occupies the Sb5+ site. After the Sc3+-In3+ substitution, the emission characteristic of the original Mg2InSbO6:Mn4+ is regulated and effectively red-shifted, and the extruded [MnO6] octahedron present distorted due to the aberration of the near-neighboring lattice sites of Mn4+. Through the Sc3+-In3+ substitution and Li+ compensation, the optimal thermal stability at 423 K is enhanced by 19.1% compared with that of Mg2InSbO6:Mn4+. Surprisingly, the designed Mg2In0.3Sc0.7SbO6:0.003Mn4+,Li+ phosphor exhibits excellent quantum yield (82.02%) and high color purity (97.3%), which is higher than most of the reported Mn4+-doped phosphors. Moreover, the growth of sweet potatoes by combining the plant growth illumination device encapsulated by the phosphor is implemented. The relevant growth parameters further confirm that the designed phosphors have a great potential application in the field of plant growth lighting.