Strong and Stable Visible Luminescence from Mesoporous MCM-41 Molecular Sieves

Abstract

This investigation describes the red photoluminescence (PL) properties of MCM-41 following annealing. Freshly prepared samples were annealed in an atmosphere of hydrogen for 30 min at various temperatures. The stability of PL of MCM-41 was founded to be improved by annealing at 500°C. The PL intensity of such samples is 30 times stronger than that of the untreated sample. The hydrogen atoms are passivating agents that terminate the dangling bonds that cover the surface of MCM-41 and effectively enhance the luminescence efficiency. Time-resolved photoluminescence was measured. The results indicate that higher luminescence efficiency accompanies longer luminescence. Accordingly, annealing in hydrogen provides a useful method for improving the intensity and stability of visible luminescence in MCM-41. © 2006 The Electrochemical Society. All rights reserved.