On the Urbach’s formula for evaluation of electron trapping parameter：The case of persistent luminescent materials

• Published in: Journal of rare earths Vol. 35; no. 8; pp. 733 - 738
• Main Authors: Chandrasekhar, Ngangbam, Singh, K. Bishal, Gartia, R.K.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.08.2017
• Subjects: afterglow; electron-trapping parameter; glow-in-the-dark phosphor; rare earths; Urbach's formula; 公式; 参数评价; 峰值温度; 曲线拟合; 热释光; 电子俘获; 研究人员; 长余辉发光材料; afterglow; glow-in-the-dark phosphor; electron-trapping parameter; Urbach's formula; rare earths
• ISSN: 1002-0721; 2509-4963
• DOI: 10.1016/S1002-0721(17)60970-0

Urbach’s formula for evaluation of electron trapping parameter that happens to be the earliest has emerged as a popular method amongst researchers of persistent luminescence. In this study, we analysed the thermoluminescence curves of glow-in-the-dark phosphors. Those included some curves recorded by us and others that solely used the Urbach’s formula. Using the parameter obtained by rigorous analysis by fitting the whole TL curves, we presented a comprehensive picture of the potentialities and limitations of the simple Urbach’s relation E=T_m/500, where E is the trap-depth and T_m the peak temperature in absolute scale, first proposed by Urbach in 1930. Some simple thumb rules on the use of the formula were presented for beginners as well as non-specialists so that entry of physically unrealistic data into the literature was prevented.