Controlling the channel diameter of the mesoporous molecular sieve MCM-41

Nanoconfined LiBH4 and Enhanced Mobility of Li+ and BH4– Studied by Solid-State NMR

“…MCM-41 was synthesized according to a procedure described by Cheng et al 43 using cetyltrimethylammonium bromide (CTAB, Aldrich) as template, Aerosil 380 (Evonik) as silica source, and tetramethylammonium hydroxide (TMAOH, 25% Aldrich) as base. 6.28 g of CTAB was dissolved in a solution containing 55.37 g of water and 6.07 g of TMAOH.…”

An Overview of Zeolite, Zeotype and Mesoporous Solids Chemistry: Design, Synthesis and Catalytic Properties

“…[37] Similar results were obtained by Cheng et al, where the pure silica MCM-41 channel diameter was varied between 26.1 and 36.5 Å , and the wall thickness was varied between 13.4 and 26.8 Å , simply by using different synthesis temperatures (70-200 C) and/or reaction times. [38] In general, MCM-41 with wider pores, thicker walled channels and higher degrees of polymerization were obtained for longer reaction times. The MCM-41 structure with the thickest walls (26.8 Å ) could withstand temperatures as high as 1000 C without disintegration.…”

“…There is, however, an upper limit to the number of neutral amine molecules the micelles can accommodate in their core, leading to an upper limit in the swelling effect. [38] Particle size is of particular importance for mesoporous materials containing unidirectional channels, such as MCM-41. If the mesopores are long, which might be the case in large particles, diffusion limitations could occur and in these cases it is preferable to have a very small particle size.…”

Ordered Porous Nanomaterials: The Merit of Small

“…In 1992, following up on Japanese researchers which hinted at the possibility of the existence of ordered mesoporous phases [138], a research group from Mobil Oil Corp. reported a material which possessed pores which were regularly spaced with a hexagonal array and a size of 3 nm. This material was named MCM-41 (from Mobil Crystalline Material) [4] and the interest it attracted has increased throughout the years after its discovery due to the fact the pore size may be tuned from 1.4 to 10 nm depending on the synthesis conditions [139,140] and the novel possibilities it brought forth in the fields of catalysis [141], in large molecules separation, or in host-guest reactions [142]. The discovery of the MCM-41 mesoporous silica, and the family of materials derived from it, gave rise to the formation of a new series of materials normally referred to as nanostructured materials or ordered mesoporous materials (OMMs) [143].…”