Abstract:
Ultra-high thermally stable Ca2MgWO6:xSm3+ (x = 0.5, 0.75, 1, 1.25, and 1.5 mol%) double perovskite phosphors were synthesized through solid-state reaction method. Product formation was confirmed by comparing the X-ray diffraction (XRD) patterns of the phosphors with the standard reference file. The structural, morphological, thermal, and optical properties of the prepared phosphor were examined in detail using XRD, Fourier transform infrared spectra, scanning electron microscopy, diffused reflectance spectra, thermogravimetric analysis (TGA), photoluminescence emission, and temperature-dependent PLE (TDPL). It was seen that the phosphor exhibited emission in the reddish region for the near-ultraviolet excitation with moderate Colour Rendering Index values and high colour purity. The optimized phosphor (x = 1.25 mol%) was found to possess a direct optical band gap of 3.31 eV. TGA studies showed the astonishing thermal stability of the optimized phosphor. Additionally, near-zero thermal quenching was seen in TDPL due to elevated phonon-assisted radiative transition. Furthermore, the anti-Stokes and Stokes emission peaks were found to be sensitive toward the temperature change and followed a Boltzmann-type distribution. All these marked properties will make the prepared phosphors a suitable candidate for multifield applications and a fascinating material for further development.
摘要:
通过固态反应法合成了超高热稳定的Ca2MgWO6:xSm3(x=0.5、0.75、1、1.25和1.5mol%)双钙钛矿荧光粉。通过将磷光体的X射线衍射(XRD)图案与标准参考文件进行比较来确认产物形成。结构,形态学,热,用XRD对所制备的荧光粉的光学性能进行了详细的研究,傅里叶变换红外光谱,扫描电子显微镜,漫反射光谱,热重分析(TGA),光致发光发射,和温度相关的PLE(TDPL)。可以看出,对于近紫外激发,磷光体在微红色区域显示出发射,具有中等的显色指数值和高色纯度。发现优化的磷光体(x=1.25mol%)具有3.31eV的直接光学带隙。TGA研究表明优化的磷光体具有惊人的热稳定性。此外,由于声子辅助的辐射跃迁升高,在TDPL中观察到接近零的热猝灭。此外,发现反斯托克斯和斯托克斯发射峰对温度变化敏感,并遵循玻尔兹曼型分布。所有这些显著的性质将使所制备的磷光体成为多场应用的合适候选物和用于进一步开发的令人着迷的材料。