White Photoluminescence Properties of Carbon-Containing Porous Silica Synthesized from Denatured Collagen / Silica Composite

Abstract

Recently, carbon-containing silica has attracted much attention due to its white photoluminescence property under UV light irradiation at room temperature. We have previously reported that microporous silica was successfully synthesized by using collagen as a template. In the removal process of collagen used as a template by calcination at high temperature, we confirmed that carbon-containing microporous silica could be synthesized by controlling calcination temperature and time. In the present study, carbon-containing microporous silica with various carbon contents were synthesized by calcination of collagen / silica composite and their white photoluminescence property was investigated. The carbon-containing microporous silica exhibited broad fluorescence spectra in the visible light region by excitation of UV light. As the carbon content decreases, the white photoluminescence property of the samples became higher, and when the carbon content was about 0.1 wt%, the sample showed the highest performance, while silica without carbon did not show the white photoluminescence property. This result suggested that carbon present into micropore of porous silica is an important role for the white photoluminescence property. It was also suggested from various spectroscopic measurements that small carbon clusters were presented in the micropore of porous silica.