Synthesis and photoluminescence properties of novel red-emitting phosphor SrAl3BO7:Mn4+ with enhanced emission by Mg2+/Zn2+/Ca2+ incorporation for plant growth LED lighting

Indoor cultivation has attracted more and more concerns in the last few years. Searching for ideal red-emitting phosphors for this application has been a great challenge. In this paper, a novel red-emitting phosphor SrAl 3 BO 7 :Mn 4+ (SABO:Mn 4+ ) had been synthesized through a modified hydrothermal reaction method for the first time. Three kinds of effect parameters, including hydrothermal reacting time, sintering temperature and Mn 4+ doping concentration, were comprehensively considered to optimize the phase purity and luminescent properties of the SABO:Mn 4+ phosphor. Besides, the luminescent properties of SABO:Mn 4+ was systematically investigated through UV–vis absorption spectra , PLE and PL spectra, CIE chromaticity coordinate and decay times. The excitation band of this phosphor locates in the wavelength range of 250–550 nm, resulting from Mn 4+ → O 2− charge transfer and electron transitions from 4 A 2 – 4 T 1 , 2 T 2 and 4 T 2 energy levels. Meanwhile, a sharp emission band is detected from 600 to 700 nm with two emission peaks located at 648 and 662 nm, which is assigned to 2 E → 4 A 2 characteristic transition of Mn 4+ . In addition, Mg 2+ /Zn 2+ /Ca 2+ are co-doped as charge compensators to improve the luminescent properties of SABO:0.03Mn 4+ . The impacts of doping concentration of Mg 2+ /Zn 2+ /Ca 2+ on the photoluminescent intensity, QE and thermal stability of SABO:0.03Mn 4+ phosphor is investigated carefully. The corresponding mechanism is discussed via decay times, EPR spectra and configurational coordinated diagram. More importantly, the EL spectrum of as-fabricated pc-LED device matches well with the absorption of plant pigments, demonstrating this novel phosphor can regard as a promising red-emitting luminescent material to meet the light requirement in plant growth LED lighting.