More specifically, by starting from the fiber producing condition

More specifically, by starting from the fiber producing conditions, we will examine the influence of acid type and content (HCl, HNO3, and H2SO4), silica precursor type and hydrophobicity (tetrabutyl orthosilicate (TBOS) and tetraethyl orthosilicate (TEOS)), and surfactant type (ionic: cyteltrimethlammonium bromide (CTAB); and nonionic: Tween 20 and Tween 80) on the product type and structural properties. Most of these

variables, except the second one [36], are being tested for the first time. Mesoporous silica products have been grown quiescently for a sufficient period of time and were #BIBW2992 order randurls[1|1|,|CHEM1|]# then tested by nitrogen porosimetry, electron microscopy, and X-ray diffraction (XRD) to characterize the morphology. These results were used to understand general features of the quiescent interfacial method and its products. Methods Materials TEOS (Si(OCH2CH3)4, 98%) and TBOS (Si(CH3CH2CH2CH2O)4, 97%) obtained from Sigma-Aldrich (St. Louis, MO, USA) were used as silica sources. Three surfactants were employed: CTAB (from Sigma Aldrich) cationic surfactant and two poly(ethylene oxide) (PEO)-based nonionic surfactants, PEO sorbitan monolaurate (known as Tween 20, from GCC, UK) and PEO sorbitan monooleate (known as Tween 80, from VWR, USA). Analytical grade hydrochloric (37%) and nitric (65%) acids were diluted to 6 M for experimental use. All dilutions and reactions were undertaken using deionized

water. Synthesis A summary of samples and growth variables of this work is given in CFTRinh-172 Table 1. Mesoporous silica fiber (MSF) sample that yields ordered mesoporous silica fibers will be used as a reference for comparison of variable outputs. Starting from the MSF molar recipe (100 H2O/3.34 HCl/0.026

CTAB/0.05 TBOS), other samples were pursued by exchanging the corresponding variable. Samples MS7 and MS12 comprise multiple runs prepared under a range of acid molar ratios: 0.2 to 3.34 nitric acid and 1.0 to 3.34 sulfuric acid, respectively. The low-acid content through of samples MS7 and MS12 was reported earlier but was not fully interpreted [43]. These results were added to this paper to provide a comprehensive analysis. The quiescent interfacial growth of mesoporous silica in a beaker is illustrated in Figure 1. The water phase is a hydrophilic mixture containing deionized water, surfactant, and acid catalyst, while the silica phase consists of the silica precursor which is generally hydrophobic to slow down its diffusion into the water phase. Table 1 A summary of samples and molar ratios per 100 mol of water Sample Acid Surfactant Silica source   HA NA SA CTAB T20 T80 TBOS TEOS MSF 3.34     0.026     0.05   MS-7   0.20 to 3.34   0.026     0.05   MS-12     1.00 to 3.34 0.026     0.05   MS-4 3.34     0.026       0.08 MS-6b   3.41   0.026       0.08 MS-5a 3.34       0.01     0.05 MS-5b 3.34         0.01   0.

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