Towards Inorganic Porous Materials by Design: Looking for New Architectures

Abstract

Crystalline porous materials, such as zeolites and metal‐organic frameworks (MOFs), possess a regular and well‐defined system of pores. While zeolites have been known for a long time and are widely used in industry, MOFs are still a new type of compounds with a huge potential for numerous applications. MOFs and zeolites may feature certain similarities as well as large differences, but concepts such as flexibility of the framework, thermodynamic versus kinetic control of the crystallization or stabilizing effect of guest species are key issues in both fields. This article presents a vision on the state of the art of such materials.

Driving the Crystallization of Zeolites

“…We have argued that the existence of a flexibility window may enhance the chance of achieving an optimal host‐guest fit and, hence, of providing enough stabilization to make the material reachable for crystallization . And we have also argued that the flexibility that matters is that of the material that actually crystallizes (the as‐made material, rather than the calcined one), so that host‐guest interactions, including the Zicovich‐Wilson effect, may provide additional flexibility to otherwise too rigid frameworks.…”

A Pure Silica Chiral Polymorph with Helical Pores

“…Silica-STW has no "flexibility window", [13] and its feasibility has been explicitly ruled out on the basis of molecular mechanics calculations. [16] Conversely, the lack of such a window would translate into a low probability for finding favorable hostguest interactions unless a particularly suitable SDA could adequately fit into the voids of the rigid framework. [16] Conversely, the lack of such a window would translate into a low probability for finding favorable hostguest interactions unless a particularly suitable SDA could adequately fit into the voids of the rigid framework.…”

Synthesis and Characterization of Al-TON Zeolite Using a Dialkylimizadolium as Structure-Directing Agent

“…[8][9][10] Depending on the characteristics of these organic molecules (size, flexibility, and hydrophobicity), zeolites with different structural characteristics can be obtained. [11][12][13][14] Imidazolium compounds (generally known as ionic liquids) have gained attention in recent years because their structures are similar to traditional used OSDA and they possess high thermal stability, negligent vapor pressure, the possibility of modification and environmental appeal.…”