Journal of Colloid and Interface Science 326 (2008) 439–444 Contents lists available at ScienceDirect Journal of Colloid and Interface Science www.elsevier.com/locate/jcis Synthesis of ordered mesoporous silica membrane on inorganic hollow fiber Jiansheng Li, Yan Zhang, Yanxia Hao, Jiangyan Zhao, Xiuyun Sun, Lianjun Wang ∗ Department of Environmental Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, People’s Republic of China article info abstract Article history: Received 4 March 2008 Accepted 4 June 2008 Available online 3 August 2008 Keywords: Synthesis Mesoporous membranes Alumina hollow fiber Filtration technique Evaporation-induced self-assembly (EISA) This paper reports on a new method for the preparation of mesoporous silica membranes on alumina hollow fibers. A surfactant–silica sol is filled in the lumen of an α-alumina hollow fiber. The filtration technique combined with an evaporation-induced self-assembly (EISA) process results in the formation of a continuous ordered mesoporous silica layer on the outer side of α-alumina hollow fibers. X-ray diffraction (XRD), transmission electron microscopy (TEM), and nitrogen isothermal adsorption measurements reveal that these membranes possess hexagonal (P6mm) mesostructures with pore diameters of 4.48 nm and BET surfaces of 492.3 m 2 g −1 . Scanning electron microscopy (SEM) studies show that the layers are defect free and energy-dispersive spectroscopy (EDS) mapping images further confirm the formation of continuous mesoporous silica layer on the outer side of α-alumina hollow fibers. Nitrogen and hydrogen permeance tests show that the membranes are defect free.  2008 Elsevier Inc. All rights reserved. 1. Introduction Surfactant-templated mesoporous silica is a promising mem- brane material because of its orderly arranged mesopores with a uniform pore diameter and an enormous surface area and pore vol- ume. There are several advantages for preparing mesoporous sil- ica membranes using a surfactant-templated method. For example, there is the potential to prepare membranes with a narrow pore size distribution, similar to what has been achieved in powder for- mation for which pore size control within the 2–10 nm size range has been demonstrated [1,2]. Additionally, under specific synthe- sis conditions, the surfactant assemblies can arrange themselves crystallographically, yielding the potential to control pore orienta- tion [3]. Due to the enormous surface area and uniform pore diameter which mesoporous silica possesses this material has gained con- siderable attention for use in high permeance and highly selective membranes. Previous research has been carried out on the synthe- sis of ordered mesoporous silica membranes on dense substrates such as glass [4–8], silicon wafers [7–10], petri dishes [11], and tin-doped indium (ITO) [12]. The challenge in making a thin mem- brane onto porous supports is that the surfactant-templated silica sol tends to penetrate into the pores of the support instead of forming a thin layer on the surface of coarse supports. Recently, many attempts have been made on the synthesis of mesoporous * Corresponding author. Fax: +86 25 84315518. E-mail address: wanglj@mail.njust.edu.cn (L. Wang). membranes on porous substrates including stainless steel [13], and especially ceramic materials [14–16]. Generally, the porous ceramic substrates used for supports of mesoporous silica membranes are tubes [14,15] with diameters of at least several millimeters or flat disks [17–19]. Consequently, the resulting membranes have low surface area to volume ratios, typ- ically a maximum of 100 m 2 m −3 in a membrane module. This limitation of low surface area to volume ratios is most evident in catalytic membranes reactors, where it is desirable to maximize the area of the membrane module to increase the permeation rate and remove the product species from the reaction zone. A hollow fiber configuration can provide higher surface area to volume ra- tios than disk or tube configurations in a membrane module [20]. For ceramic hollow fiber substrates, the surface area to volume ratios as high as 1000 m 2 m −3 can be easily obtained. Many ef- forts have been made to develop novel ceramic hollow fibers. Recently different hollow fiber ceramic membranes have been suc- cessfully prepared using phase-inversion spinning/sintering tech- nology [21–23]. The present paper reports a first effort in the synthesis of ordered mesoporous silica membranes on the outer side of α- alumina hollow fibers by a filtration technique combined with an evaporation-induced self-assembly (EISA) process. The continuous mesoporous silica membrane supported by α-alumina hollow fiber has been prepared using a triblock copolymer surfactant, Pluronic P123, and an oligometric alkyl-ethylene oxide surfactant, Brij 35 (C 12 H 25 O 23 ), as the cotemplate. The properties and microstructure of the prepared membrane and its formation mechanism were in- vestigated. 0021-9797/$ – see front matter  2008 Elsevier Inc. All rights reserved. doi:10.1016/j.jcis.2008.06.037