The increasing demand for high-contrast biological imaging,non-destructive testing,and infrared night vision can be addressed by the development of high-performance NIR light-emitting materials.Unlike lanthanide(Ln^(3...The increasing demand for high-contrast biological imaging,non-destructive testing,and infrared night vision can be addressed by the development of high-performance NIR light-emitting materials.Unlike lanthanide(Ln^(3+))with sharp-line multiplets and isolated Cr^(3+)with NIR-I emission,this study reports the first-ever NIR-Ⅱ broadband luminescence based on the intervalence charge transfer(IVCT)of Cr^(3+)-Cr^(3+)aggregation in gallate magentoplumbite.In particular,LaMgGa11O19:0.7Cr^(3+)exhibits dual-emission(NIR-I,890 nm and NIR-Ⅱ,1200 nm)with a full width at half maximum(FWHM)of 626 nm under 450 nm blue LED excitation.Moreover,this dual-emission exhibits anti-thermal quenching behavior(432%@290 K),attributed to the energy transfer among multiple Cr^(3+)centers.Cryogen absorption spectra,lifetimes decay(2.3 ms),and electron paramagnetic experiments reveal the NIR-Ⅱ luminescence of the Cr^(3+)-Cr^(3+)→Cr^(2+)-Cr^(4+)IVCT transition.The application of LaMgGa_(11)O_(19)∶0.7Cr^(3+)in NIR-Ⅱ biological imaging as an optical contrast agent,non-destructive testing,and night vision is demonstrated.This work provides new insights into broadband NIR-Ⅱ luminescence under UV-NIR excitation based on the IVCT of Cr^(3+)-Cr^(3+)aggregation.展开更多
基金This work is supported by the National Natural Science Foundations of China(Nos.51972020,12274023)。
文摘The increasing demand for high-contrast biological imaging,non-destructive testing,and infrared night vision can be addressed by the development of high-performance NIR light-emitting materials.Unlike lanthanide(Ln^(3+))with sharp-line multiplets and isolated Cr^(3+)with NIR-I emission,this study reports the first-ever NIR-Ⅱ broadband luminescence based on the intervalence charge transfer(IVCT)of Cr^(3+)-Cr^(3+)aggregation in gallate magentoplumbite.In particular,LaMgGa11O19:0.7Cr^(3+)exhibits dual-emission(NIR-I,890 nm and NIR-Ⅱ,1200 nm)with a full width at half maximum(FWHM)of 626 nm under 450 nm blue LED excitation.Moreover,this dual-emission exhibits anti-thermal quenching behavior(432%@290 K),attributed to the energy transfer among multiple Cr^(3+)centers.Cryogen absorption spectra,lifetimes decay(2.3 ms),and electron paramagnetic experiments reveal the NIR-Ⅱ luminescence of the Cr^(3+)-Cr^(3+)→Cr^(2+)-Cr^(4+)IVCT transition.The application of LaMgGa_(11)O_(19)∶0.7Cr^(3+)in NIR-Ⅱ biological imaging as an optical contrast agent,non-destructive testing,and night vision is demonstrated.This work provides new insights into broadband NIR-Ⅱ luminescence under UV-NIR excitation based on the IVCT of Cr^(3+)-Cr^(3+)aggregation.
