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Herausgeber: John Wiley & Sons
Kategorie: Wissenschaft und neue Technologien
Serie: Inorganic Chemistry: A Textbook Series
Sprache: Englisch

Beschreibung

The first comprehensive textbook on the timely and rapidly developing topic of inorganic porous materials This is the first textbook to completely cover a broad range of inorganic porous materials. It introduces the reader to the development of functional porous inorganic materials, from the synthetic zeolites in the 50's, to today's hybrid materials such as metal-organic frameworks (MOFs), covalent organic frameworks (COFs) and related networks. It also provides the necessary background to understand how porous materials are organized, characterized, and applied in adsorption, catalysis, and many other domains. Additionally, the book explains characterization and application from the materials scientist viewpoint, giving the reader a practical approach on the characterization and application of the respective materials. Introduction to Inorganic Porous Materials begins by describing the basic concepts of porosity and the different types of pores, surfaces, and amorphous versus crystalline materials, before introducing readers to nature's porous materials. It then goes on to cover everything from adsorption and catalysis to amorphous materials such as silica to inorganic carbons and Periodic Mesoporous Organosilicas (PMOs). It discusses the synthesis and applications of MOFs and the broad family of COFs. It concludes with a look at future prospects and emerging trends in the field. * The only complete book of its kind to cover the wide variety of inorganic and hybrid porous materials * A comprehensive reference and outstanding tool for any course on inorganic porous materials, heterogeneous catalysis, and adsorption * Gives students and investigators the opportunity to learn about porous materials, how to characterize them, and understand how they can be applied in different fields Introduction to Inorganic Porous Materials is an excellent book for students and professionals of inorganic chemistry and materials science with an interest in porous materials, functional inorganic materials, heterogeneous catalysis and adsorption, and solid state characterization techniques.

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Leseprobe

Inorganic Chemistry

A Wiley Series of Advanced Textbooks

ISSN: 1939‐5175

Editorial Board

David Atwood, University of Kentucky, USA

Bob Crabtree, Yale University, USA

Gerd Meyer, Iowa State University, USA

Derek Woollins, University of St. Andrews, UK

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The Organometallic Chemistry of N‐heterocyclic Carbenes

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Bioinorganic Chemistry: Inorganic Elements in the Chemistry of Life, An Introduction and Guide, 2nd Edition

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Structural Methods in Molecular Inorganic Chemistry

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Introduction to Coordination Chemistry

Geoffrey Alan Lawrance; ISBN: 978‐0‐470‐51931‐8

Chirality in Transition Metal Chemistry

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Bioinorganic Vanadium Chemistry

Dieter Rehder; ISBN: 978‐0‐470‐06516‐7

Inorganic Structural Chemistry 2nd Edition

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Lanthanide and Actinide Chemistry

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Mass Spectrometry of Inorganic and Organometallic Compounds: Tools‐Techniques‐Tips

William Henderson & J. Scott McIndoe; ISBN: 978‐0‐470‐85016‐9

Main Group Chemistry, Second Edition

A.G. Massey; ISBN: 978‐0‐471‐19039‐5

Synthesis of Organometallic Compounds: A Practical Guide

Sanshiro Komiya; ISBN: 978‐0‐471‐97195‐5

Chemical Bonds: A Dialog

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The Molecular Chemistry of the Transition Elements: An Introductory Course

Francois Mathey & Alain Sevin; ISBN: 978‐0‐471‐95687‐7

Stereochemistry of Coordination Compounds

Alexander von Zelewsky; ISBN: 978‐0‐471‐95599‐3

For more information on this series see: www.wiley.com/go/inorganic

Introduction to Porous Materials

Edited by

Pascal Van Der Voort

Ghent University Ghent, Belgium

Karen Leus

Ghent University Ghent, Belgium

Els De Canck

Recticel NV Insulation Belgium

Copyright

This edition first published 2019

All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, except as permitted by law. Advice on how to obtain permission to reuse material from this title is available at http://www.wiley.com/go/permissions.

The right of Pascal Van Der Voort, Karen Leus and Els De Canck to be identified as the authors of this work has been asserted in accordance with law.

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In view of ongoing research, equipment modifications, changes in governmental regulations, and the constant flow of information relating to the use of experimental reagents, equipment, and devices, the reader is urged to review and evaluate the information provided in the package insert or instructions for each chemical, piece of equipment, reagent, or device for, among other things, any changes in the instructions or indication of usage and for added warnings and precautions. While the publisher and authors have used their best efforts in preparing this work, they make no representations or warranties with respect to the accuracy or completeness of the contents of this work and specifically disclaim all warranties, including without limitation any implied warranties of merchantability or fitness for a particular purpose. No warranty may be created or extended by sales representatives, written sales materials or promotional statements for this work. The fact that an organization, website, or product is referred to in this work as a citation and/or potential source of further information does not mean that the publisher and authors endorse the information or services the organization, website, or product may provide or recommendations it may make. This work is sold with the understanding that the publisher is not engaged in rendering professional services. The advice and strategies contained herein may not be suitable for your situation. You should consult with a specialist where appropriate. Further, readers should be aware that websites listed in this work may have changed or disappeared between when this work was written and when it is read. Neither the publisher nor authors shall be liable for any loss of profit or any other commercial damages, including but not limited to special, incidental, consequential, or other damages.

Library of Congress Cataloging‐in‐Publication Data

Names: Voort, P. van der (Pascal), author. | Leus, Karen, author. | Canck,

Els de, author.

Title: Introduction to Porous Materials / Pascal Van Der Voort (Ghent

University, Ghent, Belgium), Karen Leus (Ghent University, Ghent,

Belgium), Els De Canck (Recticel NV Insulation, Belgium).

Other titles: Porous materials

Description: First edition. | Hoboken, NJ : Wiley, [2019] | Includes

bibliographical references and index. |

Identifiers: LCCN 2019008194 (print) | LCCN 2019009891 (ebook) | ISBN

9781119426585 (Adobe PDF) | ISBN 9781119426707 (ePub) | ISBN 9781119426608

(hardcover)

Subjects: LCSH: Porous materials. | Mesoporous materials. | Silicates.

Classification: LCC TA418.9.P6 (ebook) | LCC TA418.9.P6 V66 2019 (print) |

DDC 620.1/16–dc23

LC record available at https://lccn.loc.gov/2019008194

Cover Design: Wiley

Cover Images: Courtesy of Pascal Van Der Voort

Preface

This book is the first of its kind to discuss the development and applications of porous materials since their early start in the 1950s until now, the end of 2018. It is intended for students interested in materials science at the Masters or undergraduate level, but it is also intended for Ph.D. students who start their research in the field of porous materials.

Surprisingly, we noted that a comprehensive overview of the most important inorganic porous materials, combined with the necessary theory and characterization methods that can be used as a complete course or introduction to the field, does not exist. There are many books and monographs, but they tend to be either a collection of individual papers with less consistency, or they are high level monographs focusing on one type of material only.

The chapters in this book are almost chronological, starting with nature's materials, and then followed by the zeolites, silicas, aluminas, and carbons. After that, we discuss the materials of the twenty‐first century; advanced carbons, PMOs (Periodic Mesoporous Organosilicas), MOFs (Metal‐Organic Frameworks), and COFs (Covalent Organic Frameworks).

We have included one “theoretical” chapter, providing the reader with a solid introduction to the models of adsorption, heterogeneous catalysis, and surface area and pore volume measurements. We believe that this chapter is necessary to be able to understand the rest of the book.

We have made the choice to integrate other theoretical sections in the materials chapters at the point where we need these techniques first. So, solid state infrared spectroscopy is discussed in the silica chapter, XRD (X‐Ray Diffraction) in the zeolite chapter, TEM (transmission electron microscopy) in the MOF chapter, and so on.

The year 1999 was a magical one; in that year, many synthetic new classes of porous materials were reported, including the very famous MOFs and the PMOs. These materials are referred to as hybrid materials, as they contain both inorganic and organic functionalities. The book ends with the COFs. These are basically organic materials, but are often researched in inorganic groups, illustrating that the divisions “organic,” “inorganic,” and “analytical” become more and more obsolete in modern science.

We hope you will enjoy this book and that you will learn a lot from it. We are open to any comments and suggestions you may have regarding the content of this book.

Pascal Van Der Voort

Karen Leus

Els De Canck

April 2019

About the Authors

Pascal Van Der Voort (1967) started his professional career in 1989 as an assistant at the University of Antwerp, preparing a Ph.D. thesis on the surface decoration of silica, using a technique called “Chemical Surface Coating.” This technique is in fact very similar to the Molecular Layering technique used in the former USSR (Malygin – Saint Petersburg) and the Atomic Layer Deposition method described by Suntola.

Throughout my research career, I have worked on almost every material that is described in this book except for the zeolites, although I was surrounded by zeolite researchers in the group in the early stages and was almost literally walled by large models of zeolites.

So, during my post‐doctoral career, lasting an astonishing 10 years, I continued to work on the beloved silica supports and went to Georgia Tech to use the surface decoration method “Molecular Designed Dispersion,” a name created by Mark White at the time. During that period the MCM‐materials (and later the SBA‐materials) broke through, and I remember looking for the original Mobil patent at Georgia Tech, using these microfilm machines that are guaranteed to give you an incredible headache. In collaboration with Galen Stucky's group, I wrote on my first paper on the MCM‐48 material for catalysis, as I already understood then the benefits of a 3D open pore structure. During a short stay in Montpellier with François Fajula and Anne Galarneau, we continued to work on this topic.

A few years later, I discovered the so‐called “Plugged Hexagonal Mesoporous Silica” (PHTS), a name too difficult to be remembered by anyone. It was a partially blocked and a partially open SBA‐15 variant and I was so proud when it got its own hysteresis loop in the latest IUPAC report on porous materials (hysteresis loop H5).

After a break, I returned to the academic world in 2006, when I was appointed Assistant Professor at Ghent University, where I founded the COMOC (Center for Ordered Materials, Organometallics, and Catalysis) in 2007. We decided to work on hybrid materials, starting with PMOs and porous phenolic resins. The group needed to be built up from scratch, but soon became sizeable with the necessary work force and instruments. So, the research on MOFs started a few years later and the most recent addition to the research are covalent organic materials. Currently, still at Ghent University as a full professor, I have published 265 papers indexed in Web of Science on silica and alumina, clays and layered double hydroxides, mesoporous ordered silicas, PMOs, MOFs, carbons and phenolic resins, COFs, and CTFs.

Els De Canck (1985) started her career at Ghent University in the COMOC group. Her Ph.D. (2013) was on the development of novel Periodic Mesoporous Organosilicas (PMOs) for heterogeneous catalysis and adsorption. She worked closely with Abdel Sayari (Ottawa) on the development of PMOs for CO2 capture and with Dolores Esquivel (Córdoba) for the catalytic applications.

The PMO group in COMOC made remarkable discoveries. We were the first to create a diastereoisomeric pure ethene bridged PMO, and were the first to report on the thiol PMO, the allyl‐ring PMO and on the easy thiol‐ene click reaction in PMO modification. We work closely with Shinji Inagaki (one of the inventors of PMOs) and with several European groups on PMO materials. Els is now (since 2017) International Lab Officer at Recticel NV Insulation, a Belgian‐founded international company researching and producing polyurethane‐based insulation materials.

Karen Leus (1985) also started her career at Ghent University in the COMOC group. Her Ph.D. (2012) was on the development of Metal–Organic Frameworks for heterogeneous catalysis. During her post‐doctorate at COMOC, she went to the labs of Herme Garcia and Avelino Corma at ITQ‐Valencia to learn more about nanoparticles in MOFs and oxidation reactions. She has focused a lot on V‐based MOFs, nanoparticles, and ALD, and on mixed‐metal MOFs to tune the breathing behavior of flexible MOFs.

In recent years, she has been focusing on Covalent Triazine Frameworks (CTFs). She did an extensive stay at the labs of Professor Markus Antonietti (MPI Potsdam) and is now initiating a research line on electrocatalysis. In her young career, she has published 50 papers so far, all indexed in the Web of Science and all on MOFs and COFs. She won the Belgian Incentive Award for young researchers.

1Nature's Porous Materials: From Beautiful to Practical

Porous materials are materials that contain voids, channels, holes, or basically pores. This type of material has always attracted a lot of attention as the presence of pores means that the material possesses an internal surface area of interest for all type of applications (see Chapter 2). Nowadays, many porous materials are made in the laboratory and can even be produced on a large industrial scale (see Chapters 3 and 4). However, many porous materials are naturally occurring and were first produced in “Nature's laboratory” without any human influence. In fact, mankind has often based the preparation procedures of synthetically porous materials on processes that occur in nature.

Nature has found a way to produce beautiful and practical porous materials and they can be very diverse: tissue or bones in the human body and animals, rocks, fruit, and so on. A general overview with some examples is presented in Figure 1.1. Besides that, mankind has found its own way to introduce porosity in many materials as some examples clearly demonstrate (Figure 1.2). Ceramics, bricks, and clothing are a few items that were developed very early.

Figure 1.1 Examples of naturally occurring porous materials: lemons, snowflakes, sea sponges, coral reef, egg shells, butterfly wings (European peacock butterfly), soil, and sandstones.

Source: All photographs are public domain.

Figure 1.2 Synthetic porous materials, all made by mankind: Concrete road, paper, fabric of clothes, chalk, ceramics, cake, bread, pottery, bricks, and artificial sponges for cleaning.

Source: All photographs are public domain.

This chapter describes a few carefully selected naturally occurring porous materials. It aims to give the reader a taste of what is available in nature. These materials are also the foundation for development of synthetic porous materials that are more elaborately described in Chapters 3–9 of this book. Silicas and zeolites are also materials that were originally found in nature before a synthetic procedure was discovered to produce them. They will not be covered in this chapter, as they are described in depth in Chapters 3 and 4.

1.1 Living Porosity

1.1.1 Butterflies

Porous materials can be found in animal and human bodies. The bones and lungs of humans are famous examples of ingenious porous structures. In particular, the bones of a human skeleton are very robust, despite their high porosity, as they must support and protect our body and vital organs, respectively. Animals can also create porous structures of very diverse and beautiful shapes. For example, sponges are multicellular organisms that have an entire body containing pores. The wings of butterflies are not only colorful and useful to fly, but they are also porous (Figure 1.3). The cuticle on the scales of these butterflies' wings is composed of nano‐ and microscale, transparent, chitin‐and‐air layered structures. Rather than absorb and reflect certain light wavelengths as pigments and dyes do, these multiscale structures cause light that hits the surface of the wing to diffract and interfere. Cross ribs that protrude from the sides of ridges on the wing scale diffract incoming light waves, causing the waves to spread as they travel through spaces between the structures. The diffracted light waves then interfere with each other so that certain color wavelengths cancel out (destructive interference) while others are intensified and reflected (constructive interference). The varying heights of the wing scale ridges appear to affect the interference such that the reflected colors are uniform when viewed from a wide range of angles.

Figure 1.3 (a) Optical image of M. menelaus; (b,c) Scanning Electron Microscope (SEM) image of the nanostructure of the wing under different magnification. (d) Optical image of P. u. telegonus; (e) SEM image of the nanostructure of the blue region; the insert in (e) is the high magnification of SEM image; (f) SEM image of the nanostructure of the fiber region; and, the insert in (f) is the high magnification of SEM image. (g) Optical image of O. c. lydius; (h,i) the SEM image of the nanostructure of the wing according to different magnification.

Source: Reproduced with permission. Taken from Ref. [1], open access: https://creativecommons.org/licenses/by/4.0/.

1.1.2 Algae

Single‐celled diatoms can also produce porous structures, however, on a very different scale. Diatoms are microalgae that can be abundantly found in, for example, oceans all around the world. They are part of the phytoplankton family and contribute a staggering 20% of total oxygen produced on our planet every year. They are very unique and useful small creatures and, moreover, they produce a porous cell wall or protective shell called a frustule [2]. The frustule consists of two overlapping structures with identical shapes but slightly different in size. They are called the thecae or valve, and a girdle band or expansion joint holds the two thecae together.

The frustule is entirely made from silica, with a very well‐defined structure and unique for every diatom species. It is estimated that approximately 200 000 separate species exist with very different frustules [3]. The dimensions of the frustules can be very different depending on the species. Pore sizes range from 3 nm up to a few hundred nm [4].

A few examples of different species are presented in Figures 1.4-1.6. These figures clearly show the different morphologies, but also diverse types of porosity. These frustules do not only have beautiful porous structures, they can also be used practically.

Figure 1.4 SEM images of purified diatom frustules of Coscinodiscus sp. (a), Melosira sp. (b) and Navicula sp. (c). Scale bar = 5 μm.

Source: Reproduced with permission of John Wiley & Sons, Ltd. Taken from Ref. [4c]

Figure 1.5 SEM images of diatom frustules after 1% HF treatment: (a) and (b) Melosira after 2 and 3 h, respectively; (c) and (d) Navicula after 1 and 2 h, respectively.

Source: Reproduced with permission of Springer Nature. Taken from Ref. [4c].

Figure 1.6 Electron micrographs of the pore structures of different diatom species: (a) Lauderia borealis; (b) Odontella sinensis; (c) Thalassiosira weissflogii; (d) Coscinodiscus granii; (e) Navicula salinarum; (f) Nitzschia sigma; (g) Stauroneis constricta. Scale bar = 5 μm (a) and 0.1 μm (b–g).

Source: Reproduced with permission of the RSC. Taken from Ref. [4b].

These algae can be produced on a large industrial scale as they possess a very fast growth rate and only need a limited amount of space. Moreover, they use carbon for photosynthesis, which also makes them very interesting. It is believed that diatoms for these reasons are a very promising alternative biomass resource to produce biofuels. Additionally, they present a new source of porous silica with very defined pore sizes and distinct morphologies. The silica source can be further used as support for all kinds of applications (Chapter 5).

As an example, here we show how we extracted the silica from algae and used it as a photocatalyst for air purification [5]. Diatom frustules were extracted from a sample containing a cultivation of Thalassiosira pseudonana in its salt water medium. After an initial washing procedure to remove the majority of the salts, an acid treatment was used to remove any remaining carbonates and partially digest the organic matter. After washing away the acid, calcination in air at 550 °C was used to completely free the frustules of organic components. The resulting pure silica sheets are shown in Figure 1.7.

Figure 1.7 Silica extracted as diatom frustules from the algae species Thalassiosira pseudonana.

Source: Reproduced with permission of Elsevier. Taken from Ref. [5].

It can be clearly seen that these silica sheets contain very uniform pores. We then deposited titania nanoparticles onto these frustule sheets. The results are shown in Figure 1.8.

Figure 1.8 TEM images of the optimized titanium functionalized frustules, showing an overview of the nanoparticles (a) and a detail of the nanoparticles contained inside the pores.

Source: Reproduced with permission of Elsevier. Taken from Ref. [5] with permission.

It is remarkable how all the titania nanoparticles are situated in the pores of the silica nanosheets. These materials were shown to be very active photocatalysts for ambient air purification, outperforming the current commercial benchmarks.

1.1.3 Bamboo

Another example of an organic source that has a high silica content are bamboo leaves. An amount of 1 g of bamboo leaves contains 0.03 g of silica. A careful extraction is again key to extract the beautiful and fluffy silica flakes as presented in Figure 1.9.

Figure 1.9 Extraction of silica out of bamboo.

As we zoom in closer on the silica that is extracted from the bamboo leaves, we can see nicely in Figure 1.10 how the silica is the exact negative replicate of the bamboo leaf.

Figure 1.10 SEM picture (×250) of pure silica extracted from a bamboo leaf.

1.2 Clay Minerals

1.2.1 Natural Clays

Clay minerals are yet a completely different type of porous materials [6]. They naturally occur in mud, soils, rocks, sediments, and so on. The materials are formed in the presence of water and are most of the time fine‐grained. They have been used by mankind for ages, especially in early civilization, to produce ceramics, but now are also used in cosmetic and pharmaceutical applications.

Figure 1.11 Classification of silicates.

Source: Adapted from Z. Adamis et al. [7].

Most clay minerals are phyllosilicates or sheet silicates (Figure 1.11). They represent an entire family of silicate materials that mainly contain aluminum, silicon, and oxygen atoms. They possess a sheet‐like structure with layers of corner sharing SiO4 tetrahedra and AlO4 octahedra (Figures 1.12 and 1.13) where the oxygen atoms are commonly used. The clay minerals are categorized according to the type of connection of the tetrahedral and octahedral layers. A 1 : 1 clay mineral consists of one tetrahedral and one octahedral group in each layer. The smectite structure, shown in Figure 1.13, is a typical example of a phyllosilicate and a 2 : 1 type of clay mineral. Here, two tetrahedral sheets are connected to each side of an octahedral sheet.

Figure 1.12 Schematic representation (a) of a tetrahedron unit and tetrahedral sheet; and (b) of an octahedron unit and octahedral sheet.

Source: Adapted from G. E. Christidis et al. [6a].

Figure 1.13 An example of a clay mineral: the Smectite structure (2 : 1 clay) with two tetrahedral sheets that sandwich one octahedral sheet within the clay‐stacking pattern.

Source: Reproduced with permission of the RSC. Redrawn from Ref. [8].

The composition of the tetrahedral and octahedral sheets will determine whether the entire layer is negatively charged or not. There are also negatively balanced clays, the Layered Doubled Hydroxides (LDH); hydrotalcites are an example. In cationic clays, a charged layer will be balanced out by small cationic species, such as Na+ or K+ atoms, that are present in the so‐called interlayer of the clay mineral. This interlayer can also contain water (Figure 1.13).

The stacking of the different layers (containing tetrahedral and octahedral sheets), vary with the interlayer will form a crystalline phyllosilicate material. Examples of 1 : 1 clay minerals are the kaolinite and serpentine group with kaolinite (Figure 1.14a) being the most famous mineral of that group. The clay minerals of this group have a general formula of Al4Si4O10(OH)8 and normally do not have any layer charge. Halloysite is the hydrated form of kaolinite and can exhibit a wide range of morphologies, such as the tubular crystals as shown in Figure 1.14b.

Figure 1.14 SEM images of the clay minerals (a) Kaolinite (pseudo hexagonal crystals) and (b) halloysite (tubular crystals).

Source: Taken from Ref. [6a].

Due to the possibility of containing cations in the interlayer, clay minerals are highly suited to being ion exchange materials in many environmental but also industrial applications [6a]. They play an important role in, for example, catalytic cracking processes. They can act as an acid catalyst as they contain both Lewis and Brønsted acid sites on the clay mineral surface [9]. Also, biological and biomedical applications have been explored with clay minerals [8]. These materials are closely related to zeolites and zeotypes (Chapter 3).

Figure 1.15 Concept of pillaring.

1.2.2 Pillared Interlayered Clays – PILCs

As ever, humans have tried to tune such clays to their specific demands. One famous example was the research into the synthesis of PILCs. This was based on the pioneering work of Richard Maling Barrer in 1955 [10]. He obtained microporous materials by replacing the interlayer exchangeable cations in the smectite montmorillonite with tetraalkylammonium ions. However, organic pillared clay minerals of this type are thermally unstable. At temperatures above 250 °C the interlayers collapse. When used below the decomposition temperature, these clays can, however, still be applied as catalysts [11] or adsorbents [12]. In the late 1970s, scientists, still in search for an answer to the need for large‐pore nanoporous materials (see Chapter 5), started investigating the possibility of creating porosity in the interlayer space of layered clay hosts by inserting inorganic polymers [13]. These PILCs are prepared by exchanging the charge‐compensating cations (e.g. Na+, K+, and Ca2+) between the swelling phylosilicate clay layers with larger polymeric or oligomeric hydroxy metal cations. Upon heating, these metal hydroxy cations undergo dehydration and dehydroxylation, whereby stable metal oxide clusters are formed (e.g. Al2O3, TiO2, Fe2O3, …). These metal oxide clusters act as pillars, keeping the silicate layers permanently separated and creating an interlayer space. In Figure 1.15 a schematic overview is given, illustrating the concept of pillaring. With these novel two‐dimensional aluminosilicates, an easy method to develop materials with pores ranging from 0.5 to 2.0 nm and surface areas up to 500 m2 g−1 was introduced. Moreover, clay minerals intercalated with inorganic species retain their porosity above 300 °C.

Ever since the first announcement of the commercial availability of PILC in 1979 [13c] their use in petroleum cracking alone has exceeded that of other catalysts. With an acidity as strong as zeolite Y (Chapter 3), PILCs demonstrate a high activity in cracking, while displaying a selectivity for larger product molecules. However, due to their low hydrothermal stability, the original objective of using these materials as catalysts for Fluid Catalytic Cracking (Chapter 3) was not achieved [14]. Nevertheless, PILCs have proved to be very interesting acid catalysts in various organic reactions [15].

However, with the discovery of a new class of ordered mesoporous aluminosilicates in 1992, namely M41S (Chapter 5) [16], a new era in ordered porous materials commenced and much of the interest in PILCs faded away.