Lattice Engineering Modulates the Optical Bandgap and Near‐Infrared Properties of BaSnO 3 :Cr 3+ Phosphors
Yuelang Yang, Juanni Tian, Zhao Li, Kunyao Wu, Weixing ChenABSTRACT
This study successfully synthesized a series of BaSnO 3 : x Cr 3+ phosphors via a high‐temperature solid‐state method. Through lattice engineering strategies, effects of Cr 3+ doping on crystal structure, optical bandgap, and near‐infrared luminescence properties of BaSnO 3 were systematically investigated. Diffuse reflectance spectroscopy (DRS) revealed that Cr 3+ doping significantly reduced the effective optical bandgap; the indirect bandgap was adjusted to 2.82 eV. Spectroscopic studies indicated that the broad excitation band between 320 and 450 nm originates from 4 A 2 → 4 T 1 ( 4 P)transition, whereas the characteristic absorption between 550 and 800 nm corresponds to Cr 3+ d‐d transitions ( 4 A 2 → 4 T 2 ). Under 350‐nm UV excitation, these phosphors exhibited near‐infrared emission with a central wavelength at 900 nm and a full width at half maximum (FWHM) of approximately 104 nm, attributed to Cr 3+ 2 E g → 4 A 2 radiative transition. This work demonstrates an effective strategy for modulating band structure and luminescent properties of perovskite oxides through lattice strain engineering, providing both theoretical and experimental guidance for designing novel near‐infrared luminescent materials.