Panda Sitakanta, Vinodkumar P, Madhusoodanan U, Panigrahi B S
Health Safety & Environment Group, Indira Gandhi Centre for Atomic Research, Homi Bhabha National Institute, Kalpakkam, 603102, Tamil Nadu, India.
Health Safety & Environment Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, 603102, Tamil Nadu, India.
Luminescence. 2019 Dec;34(8):887-894. doi: 10.1002/bio.3687. Epub 2019 Jul 21.
Ce-doped (1 × 10 to 3.0 mol%) SrBPO phosphors were synthesized using a conventional solid-state reaction route at 1273 K in an air atmosphere. Phase and morphology of the samples were studied from powder X-ray diffraction (XRD) patterns and scanning electron microscope (SEM) micrographs, respectively. The band gap energies of the pure and Ce-doped SrBPO phosphors were calculated from the recorded diffuse reflectance spectra. Photoluminescence (PL) and Ce lifetime were recorded at 300 and 77 K. Photoluminescence lifetime measurements revealed two-lifetime values for Ce at both 300 K (17 and 36 nsec) and 77 K (12 and 30 nsec), suggesting the presence of two different environments around Ce . Time-resolved emission spectroscopy (TRES) studies confirmed the presence of Ce in two different environments. In addition, SrBPO :Ce exhibited intense UV emission, signifying its possible use as an efficient sensitizer for solid-state lighting applications. The effect of γ-irradiation on PL was also determined. Thermally stimulated luminescence (TSL) glow curves of the γ-irradiated phosphor, along with trap parameters, dose-response, and the possible TSL mechanism were also investigated. Positron annihilation lifetime spectroscopy was carried out to probe defects present in undoped and Ce-doped SrBPO .
采用传统的固态反应路线，在1273K的空气气氛中合成了铈掺杂（1×10至3.0摩尔%）的SrBPO荧光粉。分别通过粉末X射线衍射（XRD）图谱和扫描电子显微镜（SEM）显微照片研究了样品的相和形貌。根据记录的漫反射光谱计算了纯SrBPO和铈掺杂SrBPO荧光粉的带隙能量。在300K和77K下记录了光致发光（PL）和铈的寿命。光致发光寿命测量显示，在300K（17和36纳秒）和77K（12和30纳秒）时铈有两个寿命值，这表明铈周围存在两种不同的环境。时间分辨发射光谱（TRES）研究证实了铈存在于两种不同的环境中。此外，SrBPO:Ce表现出强烈的紫外发射，这表明它有可能用作固态照明应用的高效敏化剂。还确定了γ辐照对PL的影响。还研究了γ辐照荧光粉的热释光（TSL）发光曲线以及陷阱参数、剂量响应和可能的TSL机制。进行了正电子湮没寿命光谱分析，以探测未掺杂和铈掺杂的SrBPO中存在的缺陷。
