Optical, spectral and thermal properties of natural pumice glass. (January 2017)

• Record Type: Journal Article
• Authors: Correcher, V.; Gomez-Ros, J.M.; Dogan, T.; Garcia-Guinea, J.; Topaksu, M.
• Is Part Of: Radiation physics and chemistry. Volume 130(2017)
• Page Start: 69
• Page End: 75
• Publication Date: 2017-01
• Subjects: Pumice -- Thermoluminescence -- Cathodoluminescence -- Kinetic parameters; Radiation chemistry -- Periodicals; Radiometry -- Periodicals; Radiation -- Periodicals; Chimie sous rayonnement -- Périodiques; 539.2
• DOI: 10.1016/j.radphyschem.2016.08.002
• Languages: English
• ISSNs: 0969-806X

Abstract

Abstract: Pumice is a natural Si-rich material displaying a complex cathodo- (CL) and thermoluminescence (TL) glow curves. The UV-IR CL emission consists of (i) a UV waveband in the range of 340–420 nm, (ii) blue band at 450–480 nm and (iii) a broad emission in the green-red region (at 550–650 nm) that could be respectively linked to Non Bridging Oxygen Hole Centers (Si–O), self-trapped excitons and point defects (Mn 2+ −0.03%- and Fe −1.15%-). Thermal treatments performed on the TL glow curves allowed us to determine that the trap system could be associated with a continuum in the trap distribution, since successive thermal pretreatments in the range of 200–310 °C induce an emission that shifts linearly to higher temperatures when the thermal pretreatment ( T stop ) is increased, while the intensity of the maxima decreases similarly to the peak area. The evaluation of the Ea values, s value and the trap system calculated by VHR, IR and Glow curve fitting methods considering three possible distribution function for n(E): gaussian, exponential and uniform, has given matching values for the 280 °C TL peak. Highlights: Pumice is a natural non-crystalline material with complex luminescence behavior. Cathodoluminescence exhibits three main wavebands in the UV, UV-blue and green-IR region. Trap structure could be associated with a continuous distribution.