Luminescence of Nanocrystalline ZnS:Pb2+

✍ Scribed by A.A. Bol; A. Meijerink

• Publisher: John Wiley and Sons
• Year: 2001
• Tongue: English
• Weight: 107 KB
• Volume: 224
• Category: Article
• ISSN: 0370-1972
• DOI: 10.1002/1521-3951(200103)224:1<173::aid-pssb173>3.0.co;2-w

✦ Synopsis

Pb 2+ is synthesised via a precipitation method. The influence of the particle size on the luminescence of nanocrystalline ZnS : Pb 2+ is studied. Depending on the excitation wavelength, nanocrystalline ZnS : Pb 2+ shows a very broad white (l exc = 380 nm) or red emission (l exc = 480 nm). The red and white emissions are assigned to charge transfer transitions involving different Pb 2+ centres. The decay kinetics of both emissions are typical for Pb 2+ (low temperature: ms, high temperature: ms) and are independent of the particle size. The quenching of luminescence with increasing temperature is explained by photoionization. The lower quenching temperature for the luminescence of larger nanoparticles is explained by quantum size effects.