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Li/Na substitution and Yb³⁺ co-doping enabling tunable near-infrared emission in LiIn₂SbO₆:Cr³⁺ phosphors for light-emitting diodes.

ABSTRACT: Near-infrared (NIR) phosphor-converted light-emitting diode (pc-LED) has great potential in non-invasive detection, while the discovery of tunable broadband NIR phosphor still remains a challenge. Here, we report that Cr³⁺-activated LiIn₂SbO₆ exhibits a broad emission band ranging from 780 to 1400 nm with a full width at half maximum (FWHM) of 225 nm upon 492 nm excitation. The emission peaks are tuned from 970 to 1020 nm together with considerable broadening of FWHM (∼285 nm) via Li/Na substitution. Depending on Yb³⁺ co-doping, a stronger NIR fluorescence peak of Yb³⁺ appears with improved thermal resistance, which is ascribed to efficient energy transfer from Cr³⁺ to Yb³⁺. An NIR pc-LED package has been finally designed and demonstrated a remarkable ability to penetrate pork tissues (∼2 cm) so that the insertion depth of a needle can be observed, indicating that the phosphor can be applied in non-destructive monitoring.

SUBMITTER: Liu G

PROVIDER: S-EPMC7995531 | biostudies-literature |

REPOSITORIES: biostudies-literature

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