WEB Advancement of ordered mesoporous silica COK-12 and its applicationsTuesday (22.09.2020) 11:20 - 11:35 Z: Special Symposia I Part of:
Ordered mesoporous silica COK-12 materials provide high surface areas due to their defined 2D hexagonally-packed cylindrical ordered mesopores with around 6 nm in diameter1. In comparison to other ordered mesoporous silica (OMS) materials, the synthesis is more sustainable, as it is performed at room temperature under mild reaction conditions. Furthermore, the synthesis is comparatively time efficient and inexpensive. Equivalent to other OMS materials, COK-12 is synthesized by a soft-templating pathway using the amphiphilic triblock copolymer P123 as structure-directing agent.
We investigated the tailoring and applicability of COK-12 by i) increasing the surface area, ii) up-scaling the synthesis, iii) pore enlargement, iv) pore modification, v) shaping, and vi) surface functionalization.
By improving the synthesis parameters as washing step and aging temperature, the specific surface area and pore volume of COK-12 have been significantly increased up to 860 m2/g and 1.23 cm3/g, respectively. Simultaneously, the pore size has been linearly adjusted between 5.7 and 8.1 nm depending on the aging temperature of 10 to 90 °C, respectively2. A large-scale production with uniform COK-12 properties has been demonstrated in batch and in quasi-continuous mode. Due to the addition of micellar swelling agents as hexane and propylene glycol, we have succeeded in the formation of mesocellular foams with “ink-bottle” shaped pores, reaching up to 8.5 nm in cell diameter and 5.3 nm in window diameter, and multilamellar vesicular configurations3. A promising approach towards industrial applicability is the shaping of the powder COK-12 to granules and monoliths. After surface functionalization of COK-12 with graphene oxide, functional organic groups or immobilization of metal oxides/nanoparticles, COK-12 has been successfully applied as adsorbent in toxic dye removal from waste water as well as support in various catalytic reactions as oxidative coupling of methane4.
1J. Jammaer, A. Aerts, J. D'Haen, J.W. Seo and J.A. Martens, Stud Surf Sci Catal 175, 2010, 681–684. 2L.M. Henning, D.D. Cubas, M.G. Colmenares, J. Schmidt, M.F. Bekheet, B.R. Pauw, A. Gurlo, U. Simon, Microporous Mesoporous Mater 280 (2019) 133–143. 3M.G. Colmenares, U. Simon, F. Schmidt, S. Dey, J. Schmidt, A. Thomas, A. Gurlo, Microporous Mesoporous Mater 267 (2018) 142–149. 4L.M. Henning, U. Simon, G.J. Smales, G. Gurlo, M. Bekheet, RSC Adv 62 (2019) 36271–36284.