LAUSR

Abstract In this paper, our effort is focused on preparation and oxygen sensing of fluorescent silicon nanoparticles (Si NPs) assembled in three kinds of mesoporous SBA-15 with different morphologies, including spherical mesoporous SBA-15 (SPSBA-15), long rod-like mesoporous SBA-15 (LRSBA-15) and hexagonal prism-like mesoporous SBA-15 (HPSBA-15). The relationship of structure and sensing properties in mesoporous materials is studied. Small angle powder X-ray diffraction (SAXRD), Fourier transform infrared spectrometer (FT-IR), Brunauer-Emmett-Teller (BET), Discrete-Fourier-Transform (DFT) analyses and X-ray photoelectron spectroscopy (XPS) are used to characterize their structural properties. The obtained mesoporous SPSBA-15, LRSBA-15 and HPSBA-15 possess abundant Si–O–Si bands of the inorganic framework and high surface-volume ratios. Particularly, mesoporous HPSBA-15 materials exhibit the largest surface areas than other two mesoporous materials. Accordingly, the adding volume of Si NPs was 8 ml in mesoporous HPSBA-15. At the same time, the hybrid materials show the shortest response time of 2.2 s and recovery time of 11.2 s. This result can be attributed to the uniform and nearly parallel porous structure of the HPSBA-15 materials supporting with large surface areas and narrow pore size distributions. Therefore, the properties in oxygen sensing can be improved by using mesoporous SBA-15 materials with larger BET surface area.