Fabrication of a micro gas chromatography column via the layer-by-layer deposition of mesoporous silica as the stationary phase.

• The LBL deposition process improved the uniformity of the stationary phase and the separation performance of C1–C4. • The resolutions and symmetries of C1–C4 were improved upon increasing the number of deposition cycles. • The resolution of C1–C2 was as high as 5.89 after 8 deposition cycles. • The tailing factors of C1–C4 were closest to 1 after 8 deposition cycles. In this paper, a micro gas chromatographic column (μGCC) was fabricated via the layer-by-layer (LBL) deposition of mesoporous silica (MS) as the stationary phase. The μGCC with embedded elliptical-cylindrical posts was fabricated by typical micro-electro-mechanical system (MEMS) techniques. The MS powder was prepared by a sol-gel method and then deposited inside the microchannels of the μGCC by LBL deposition. This process avoided the high temperature required for the sol-gel method to directly prepare MS inside the microchannel surfaces of the μGCC. Mixtures of light alkanes (C1–C4) could be separated in the μGCC. The separation results showed that the resolution between the components of the sample increased with the number of deposition cycles. When the number of deposition cycles increased from 1 to 8, the resolution of methane and ethane was increased from unseparated to 5.89. [ABSTRACT FROM AUTHOR]