Elzer Eugenia, Strobel Philipp, Weiler Volker, Amin Muhammad R, Schmidt Peter J, Moewes Alexander, Schnick Wolfgang
Department of Chemistry, University of Munich (LMU), Butenandtstrasse 5-13, (D) 81377, Munich, Germany.
Lumileds Phosphor Center Aachen, Philipsstrasse 8, 52068, Aachen, Germany.
Chemistry. 2022 Feb 24;28(12):e202104121. doi: 10.1002/chem.202104121. Epub 2022 Feb 2.
The nitridoberylloaluminate Ba [BeAl N ]:Eu and solid solutions Sr Ba [BeAl N ]:Eu (x=0.5, 1.0, 1.5) were synthesized in a hot isostatic press (HIP) under 50 MPa N atmosphere at 1200 °C. Ba [BeAl N ]:Eu crystallizes in triclinic space group (no. 2) (Z=2, a=6.1869(10), b=7.1736(13), c=8.0391(14) Å, α=102.754(8), β=112.032(6), γ=104.765(7)°), which was determined from single-crystal X-ray diffraction data. The lattice parameters of the solid solution series have been obtained from Rietveld refinements and show a nearly linear dependence on the atomic ratio Sr : Ba. The electronic properties and the band gaps of M [BeAl N ] (M=Sr, Ba) have been investigated by a combination of soft X-ray spectroscopy and density functional theory (DFT) calculations. Upon irradiation with blue light (440-450 nm), the nitridoberylloaluminates exhibit intense orange to red luminescence, which can be tuned between 610 and 656 nm (fwhm=1922-2025 cm (72-87 nm)). In contrast to the usual trend, the substitution of the smaller Sr by larger Ba leads to an inverse-tunable luminescence to higher wavelengths. Low-temperature luminescence measurements have been performed to exclude anomalous emission.
氮铍铝酸盐Ba[BeAlN]：Eu以及固溶体SrBa[BeAlN]：Eu（x = 0.5、1.0、1.5）是在热等静压机（HIP）中于50兆帕氮气气氛下、1200°C合成的。Ba[BeAlN]：Eu结晶于三斜空间群（编号2）（Z = 2，a = 6.1869(10)，b = 7.1736(13)，c = 8.0391(14) Å，α = 102.754(8)，β = 112.032(6)，γ = 104.765(7)°），这是根据单晶X射线衍射数据确定的。固溶体系列的晶格参数通过Rietveld精修获得，并显示出与原子比Sr∶Ba几乎呈线性关系。通过软X射线光谱学和密度泛函理论（DFT）计算相结合的方法研究了M[BeAlN]（M = Sr、Ba）的电子性质和带隙。在用蓝光（440 - 450 nm）照射时，氮铍铝酸盐呈现出强烈的橙色到红色发光，其发光波长可在610至656 nm之间调节（半高宽 = 1922 - 2025 cm⁻¹（72 - 87 nm））。与通常趋势相反，用较大的Ba取代较小的Sr会导致发光向更高波长的反向可调。已经进行了低温发光测量以排除异常发射。
