A High Efficiency Trivalent Chromium-Doped Near-Infrared-Emitting Phosphor and Its NIR Spectroscopy Application
journal contributionposted on 14.02.2021, 15:29 by Yunpeng Zhou, Xinjuan Li, Takatoshi Seto, Yuhua Wang
The wearable biosensing and food safety monitoring equipment requires high-brightness and thermally stable near-infrared (NIR) phosphor-converted light emitting diodes (pc-LEDs), and the performance of these pc-LEDs is highly dependent on the properties of the NIR phosphors. This work reports an ultrawide near-infrared emission phosphor Ca3Sc2Si3O12: Cr3+. Under 460 nm excitation, Ca3Sc2Si3O12: Cr3+ presents an ultrawide emission range from 650 to 900 nm. The weak absorption capacity of Cr3+ is the main factor causing its undesirable luminous efficiency. Ce3+ was introduced into the matrix as a role of sensitizer to contribute to the improvement of the absorption of Cr3+. An efficient process for energy transfer from Ce3+ to Cr3+ can be observed within the Ca3Sc2Si3O12 codoped substance with Ce3+ and Cr3+. The sample with the best doping concentration has demonstrated excellent thermal stability. At a particular temperature at 150 °C, the phenomenon of the near-infrared emission intensity is maintained at 82% at room temperature. The output power of the NIR-pc-LED based on the Ca3Sc2Si3O12: Ce3+, Cr3+ and 450 nm chip reached 21.65 mW@350 mA. The excellent performance of penetrating human tissues demonstrated by the near-infrared pc-LED was observed.
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food safety monitoring equipmentdoping concentration3 Sc 2 Si 3 O 12460 nm excitationHigh Efficiency Trivalent Chromium-...work reportsphosphor-converted lightnear-infrared pc-LED450 nm chipNIR Spectroscopy Applicationultrawide near-infrared emission ph...3 Sc 2 Si 3 O 12 codoped substancewearable biosensingCeCrultrawide emission rangeabsorption capacitynear-infrared emission intensity900 nmenergy transferoutput powerroom temperatureNIR phosphors