NaLaMgWO6:Mn4+/Pr3+/Bi3+ bifunctional phosphors for optical thermometer and plant growth illumination matching phytochrome PR and

Phytochromes PR and PFR distributed in different organs of plant can effectively absorb red and far-red light, respectively. Therefore, plant growth can be controlled by changing the ratio of red light to farred light. The emission of Pr3+ (transition from P-3(0) -> F-3(2),(3))and Mn4+(transition from (2)Eg -> (4)A(2g)) is located at the red and far-red range which matches with the absorption band of PR and PFR, respectively. Herein, NaLaMgWO6:Mn4+/Pr3+/Bi3+ phosphors with improving luminescence properties via Bi3+ doping have been successfully prepared by the sol-gel method. With the variation of temperature, the photoluminescence (PL) of Pr3+/Mn4+ (corresponding to PFR/PR) of titled phosphors can be tuned, which is very useful for controlling the plant growth. Moreover, based on the fluorescence intensity ratios (FIR) of the two activator Mn4+ and Pr3+, the maximum relative sensitivity was approximately 3.39%/K at 298 K. All the results indicated that the titled phosphor is a bifunctional material for plant growth illumination with high matching phytochrome (PR and PFR) and temperature sensing with high sensitivity. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

A Bi3+-doped NaLaMgWO6:Mn4+/Pr3+/Bi3+ phosphor with tunable photoluminescence for controlling plant growth has been successfully prepared. The maximum relative sensitivity of approximately 3.39%/K at 298 K was achieved based on the fluorescence intensity ratios of Mn4+ and Pr3+. This phosphor is a bifunctional material for plant growth illumination and temperature sensing with high sensitivity.