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Comparative study on the photoluminescent properties of siliceous MCM-41 with silica particles and xerogels

โœ Scribed by J. Zhang; J. Lin

Publisher
Elsevier Science
Year
2004
Tongue
English
Weight
354 KB
Volume
75
Category
Article
ISSN
1387-1811

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โœฆ Synopsis

The samples of as-synthesized siliceous MCM-41, extracted MCM-41, amorphous silica particles and silica xerogels were heat treated from room temperature to 1000 ยฐC. Their photoluminescence (PL) spectra at room temperature excited by 254 nm and 365 nm ultraviolet light (UV) were investigated and compared. Excited by 254 nm UV the MCM-41 samples do not display PL but amorphous silica particles and silica xerogels show PL, which changes with the heat treatment conditions for the samples. However, when excited by 365 nm UV the PL spectra for the MCM-41 and the amorphous samples are similar. The carbon impurity and E 0 center mechanisms can be ruled out as the origin of PL in siliceous MCM-41 under UV excitation. The PL of MCM-41 series samples probably originates from oxygen-related defect center like "Si-O ร… according to the present work.

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