Fluorescence emission properties of rhodamine B encapsulated organic-inorganic hybrid mesoporous silica host

Abstract Mesoporous silica material can be viewed as an ideal solid host for constructing desirable dye laser with tunable wavelength range. In this investigation, Rhodamine B molecules were successfully encapsulated into the pore of highly ordered MCM-41 and Phenyl-functionalized MCM-41 mesoporous silica by using a simple and facile postgrafting method. The as-gained Rhodamine B encapsulated mesoporous silica materials were successfully characterized by Fourier transform infrared spectroscopy, nitrogen adsorption-desorption and small angle X-ray diffraction. Particularly, the optical absorption and electrochemical behaviors investigated by UV-vis absorption spectra and electrochemical cyclic voltammogram indicate that the difference on the hydrophillic nature of different mesoporous silica hosts has great influence on the existence state of Rh B molecules, resulting lead to strong fluorescence and obvious blue-shift of the encapsulated Rhodamine B molecules in the proposed organic-inorganic hybrid mesoporous. Furthermore, it was pointed out that the significant host-guest interactions of mesoporous silica and Rhodamine B are related not only to the structure, but also to the environmental and surrounding polarity of the materials.