E-Mail Alert

Add your e-mail address to receive forthcoming issues of this journal:

Journal Browser

Journal Browser

Special Issue "Porous Materials"

Quicklinks

A special issue of Materials (ISSN 1996-1944). This special issue belongs to the section "Porous Materials".

Deadline for manuscript submissions: closed (30 October 2009)

Special Issue Editor

Guest Editor
Prof. Dr. Jonah Erlebacher

Department of Materials Science and Engineering 102 Maryland Hall, 3400 N. Charles St. Baltimore, MD 21218, USA
Website | E-Mail
Interests: nanoporous metals; kinetics of nanoscale morphological evolution; fuel cell catalysis; thin foil metallurgy; fundamentals of protein crystal growth

Special Issue Information

Dear Colleagues,

Porous materials are found in all classes of materials, from microporous zeolite ceramics, to mesoporous metals, to macroporous polymers. They are fundamental in a diverse range of applications, from structural materials to energy technologies. Recent advances in porous materials include the development of nanoporous metals by selective dissolution and their use in catalysis, and phase separation methods to make porous ceramics. This special issue of Materials will be devoted to exploring the wide range of types and applications of porous materials. Special emphasis will be devoted to new fabrication methods, new properties, and new applications of porous materials, and how these impact many different technologies.

Prof. Dr. Jonah Erlebacher
Guest Editor

Keywords

  • porous materials
  • nanoporosity
  • porous ceramics
  • porous metals
  • porous polymers
  • microporous and mesoporous materials

Published Papers (17 papers)

View options order results:
result details:
Displaying articles 1-17
Export citation of selected articles as:

Research

Jump to: Review

Open AccessArticle Towards the Development of Electrical Biosensors Based on Nanostructured Porous Silicon
Materials 2010, 3(2), 755-763; doi:10.3390/ma3020755
Received: 14 December 2009 / Revised: 12 January 2010 / Accepted: 25 January 2010 / Published: 27 January 2010
Cited by 8 | PDF Full-text (880 KB) | HTML Full-text | XML Full-text
Abstract
The typical large specific surface area and high reactivity of nanostructured porous silicon (nanoPS) make this material very suitable for the development of sensors. Moreover, its biocompatibility and biodegradability opens the way to the development of biosensors. As such, in this work the
[...] Read more.
The typical large specific surface area and high reactivity of nanostructured porous silicon (nanoPS) make this material very suitable for the development of sensors. Moreover, its biocompatibility and biodegradability opens the way to the development of biosensors. As such, in this work the use of nanoPS in the field of electrical biosensing is explored. More specifically, nanoPS-based devices with Al/nanoPS/Al and Au-NiCr/nanoPS/Au-NiCr structures were fabricated for the electrical detection of glucose and Escherichia Coli bacteria at different concentrations. The experimental results show that the current-voltage characteristics of these symmetric metal/nanoPS/metal structures strongly depend on the presence/absence and concentration of species immobilized on the surface. Full article
(This article belongs to the Special Issue Porous Materials)
Figures

Open AccessArticle Preparation and Hydrogen Absorption/Desorption of Nanoporous Palladium Thin Films
Materials 2009, 2(4), 2496-2509; doi:10.3390/ma2042496
Received: 29 October 2009 / Revised: 18 December 2009 / Accepted: 21 December 2009 / Published: 23 December 2009
Cited by 7 | PDF Full-text (1576 KB) | HTML Full-text | XML Full-text
Abstract
Nanoporous Pd (np-Pd) was prepared by co-sputtering Pd-Ni alloy films onto Si substrates, followed by chemical dealloying with sulfuric acid. X-ray diffractometry and chemical analysis were used to track the extent of dealloying. The np-Pd structure was changed from particle-like to sponge-like by
[...] Read more.
Nanoporous Pd (np-Pd) was prepared by co-sputtering Pd-Ni alloy films onto Si substrates, followed by chemical dealloying with sulfuric acid. X-ray diffractometry and chemical analysis were used to track the extent of dealloying. The np-Pd structure was changed from particle-like to sponge-like by diluting the sulfuric acid etchant. Using suitable precursor alloy composition and dealloying conditions, np-Pd films were prepared with uniform and open sponge-like structures, with interconnected ligaments and no cracks, yielding a large amount of surface area for reactions with hydrogen. Np-Pd films exhibited shorter response time for hydrogen absorption/desorption than dense Pd films, showing promise for hydrogen sensing. Full article
(This article belongs to the Special Issue Porous Materials)
Figures

Open AccessArticle Highly Loaded Fe-MCM-41 Materials: Synthesis and Reducibility Studies
Materials 2009, 2(4), 2337-2359; doi:10.3390/ma2042337
Received: 4 November 2009 / Revised: 30 November 2009 / Accepted: 14 December 2009 / Published: 15 December 2009
Cited by 3 | PDF Full-text (1389 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Fe-MCM-41 materials were prepared by different methods. The Fe was both incorporated into the structure and formed crystallites attached to the silica. High Fe content MCM-41 (~16 wt%) with retention of mesoporosity and long-range order was achieved by a range of new synthetic
[...] Read more.
Fe-MCM-41 materials were prepared by different methods. The Fe was both incorporated into the structure and formed crystallites attached to the silica. High Fe content MCM-41 (~16 wt%) with retention of mesoporosity and long-range order was achieved by a range of new synthetic methodologies: (i) by delaying the addition of Fe3+(aq) to the stirred synthesis gel by 2 h, (ii) by addition of Fe3+ precursor as a freshlyprecipitated aqueous slurry, (iii) by exploiting a secondary synthesis with Si-MCM-41 as SiO2 source. For comparative purposes the MCM-41 was also prepared by incipient wetness impregnation (IWI). Although all these synthesis methods preserved mesoporosity and long-range order of the SiO2 matrix, the hydrothermally-fabricated Fe materials prepared via the secondary synthesis route has the most useful properties for exploitation as a catalyst, in terms of hydrothermal stability of the resulting support. Temperatureprogrammed reduction (TPR) studies revealed a three-peak reduction pattern for this material instead of the commonly observed two-peak reduction pattern. The three peaks showed variable intensity that related to the presence of two components: crystalline Fe2O3 and Fe embedded in the SiO2 matrix (on the basis of ESR studies). The role of secondary synthesis of Si-MCM-41 on the iron reducibility was also demonstrated in IWI of sec-Si-MCM-41. Full article
(This article belongs to the Special Issue Porous Materials)
Figures

Open AccessArticle A Self-Propagating Foaming Process of Porous Al-Ni Intermetallics Assisted by Combustion Reactions
Materials 2009, 2(4), 2360-2368; doi:10.3390/ma2042360
Received: 29 October 2009 / Revised: 3 December 2009 / Accepted: 14 December 2009 / Published: 15 December 2009
Cited by 1 | PDF Full-text (822 KB) | HTML Full-text | XML Full-text
Abstract
The self-propagating foaming process of porous Al-Ni intermetallics was investigated. Aluminum and nickel powders were blended, and titanium and boron carbide powders were added as reactive exothermic agents. The blended powder was extruded to make a rod-shape precursor. Only one end of the
[...] Read more.
The self-propagating foaming process of porous Al-Ni intermetallics was investigated. Aluminum and nickel powders were blended, and titanium and boron carbide powders were added as reactive exothermic agents. The blended powder was extruded to make a rod-shape precursor. Only one end of the rod precursor was heated to ignite the reaction. The reaction propagated spontaneously throughout the precursor. Pore formation took place at the same time as the reaction occurred. Adding the exothermic agent was effective to increase the porosity. Preheating the precursor before the ignition was also very effective to produce porous Al-Ni intermetallics with high porosity. Full article
(This article belongs to the Special Issue Porous Materials)
Open AccessArticle Porous Ba Ferrite Prepared from Wood Template
Materials 2009, 2(4), 1923-1928; doi:10.3390/ma2041923
Received: 5 November 2009 / Revised: 16 November 2009 / Accepted: 19 November 2009 / Published: 20 November 2009
Cited by 4 | PDF Full-text (512 KB) | HTML Full-text | XML Full-text
Abstract
Ba ferrite materials with porous microstructures were prepared from a natural cedar wood template in order to investigate new electromagnetic shielding materials. The wood templates were infiltrated with barium nitrate and iron nitrate solutions (molar ratio = 1:12) and dried to form ferrite
[...] Read more.
Ba ferrite materials with porous microstructures were prepared from a natural cedar wood template in order to investigate new electromagnetic shielding materials. The wood templates were infiltrated with barium nitrate and iron nitrate solutions (molar ratio = 1:12) and dried to form ferrite gel, then, they were sintered in air at a temperature between 800 °C and 1400 °C. The 1-dimensional porous structures were retained after sintering and the pore size was approximately 10–20 μm. These ferrites show large coercive force and anisotropy field. The largest coercive force was obtained for the specimen sintered at 800 °C. Full article
(This article belongs to the Special Issue Porous Materials)
Open AccessArticle Porous Thermoelectric Materials
Materials 2009, 2(3), 903-910; doi:10.3390/ma2030903
Received: 20 June 2009 / Revised: 25 July 2009 / Accepted: 28 July 2009 / Published: 5 August 2009
Cited by 12 | PDF Full-text (1391 KB) | HTML Full-text | XML Full-text
Abstract
Thermoelectric materials are sometimes prepared using a sintering process in which the achievement of a high density is often one of the objectives. However, it has recently been shown that the introduction of a highly porous material is desirable in synthetic transverse thermoelements.
[...] Read more.
Thermoelectric materials are sometimes prepared using a sintering process in which the achievement of a high density is often one of the objectives. However, it has recently been shown that the introduction of a highly porous material is desirable in synthetic transverse thermoelements. Porosity may also be an advantage in conventional longitudinal thermoelectric modules in which a high thermal flux density creates problems, but heat transfer within the pores can degrade the thermoelectric figure of merit. The amount of this degradation is calculated and it is shown that it can be small enough to be acceptable in practical devices. Full article
(This article belongs to the Special Issue Porous Materials)

Review

Jump to: Research

Open AccessReview Macroporous Semiconductors
Materials 2010, 3(5), 3006-3076; doi:10.3390/ma3053006
Received: 19 February 2010 / Revised: 30 March 2010 / Accepted: 30 April 2010 / Published: 7 May 2010
Cited by 37 | PDF Full-text (5734 KB) | HTML Full-text | XML Full-text
Abstract
Pores in single crystalline semiconductors come in many forms (e.g., pore sizes from 2 nm to > 10 µm; morphologies from perfect pore crystal to fractal) and exhibit many unique properties directly or as nanocompounds if the pores are filled. The various kinds
[...] Read more.
Pores in single crystalline semiconductors come in many forms (e.g., pore sizes from 2 nm to > 10 µm; morphologies from perfect pore crystal to fractal) and exhibit many unique properties directly or as nanocompounds if the pores are filled. The various kinds of pores obtained in semiconductors like Ge, Si, III-V, and II-VI compound semiconductors are systematically reviewed, emphasizing macropores. Essentials of pore formation mechanisms will be discussed, focusing on differences and some open questions but in particular on common properties. Possible applications of porous semiconductors, including for example high explosives, high efficiency electrodes for Li ion batteries, drug delivery systems, solar cells, thermoelectric elements and many novel electronic, optical or sensor devices, will be introduced and discussed. Full article
(This article belongs to the Special Issue Porous Materials)
Open AccessReview Porous Silicon—A Versatile Host Material
Materials 2010, 3(2), 943-998; doi:10.3390/ma3020943
Received: 31 October 2009 / Revised: 22 January 2010 / Accepted: 2 February 2010 / Published: 3 February 2010
Cited by 86 | PDF Full-text (5214 KB) | HTML Full-text | XML Full-text
Abstract
This work reviews the use of porous silicon (PS) as a nanomaterial which is extensively investigated and utilized for various applications, e.g., in the fields of optics, sensor technology and biomedicine. Furthermore the combination of PS with one or more materials which are
[...] Read more.
This work reviews the use of porous silicon (PS) as a nanomaterial which is extensively investigated and utilized for various applications, e.g., in the fields of optics, sensor technology and biomedicine. Furthermore the combination of PS with one or more materials which are also nanostructured due to their deposition within the porous matrix is discussed. Such nanocompounds offer a broad avenue of new and interesting properties depending on the kind of involved materials as well as on their morphology. The filling of the pores performed by electroless or electrochemical deposition is described, whereas different morphologies, reaching from micro- to macro pores are utilized as host material which can be self-organized or fabricated by prestructuring. For metal-deposition within the porous structures, both ferromagnetic and non-magnetic metals are used. Emphasis will be put on self-arranged mesoporous silicon, offering a quasi-regular pore arrangement, employed as template for filling with ferromagnetic metals. By varying the deposition parameters the precipitation of the metal structures within the pores can be tuned in geometry and spatial distribution leading to samples with desired magnetic properties. The correlation between morphology and magnetic behaviour of such semiconducting/magnetic systems will be determined. Porous silicon and its combination with a variety of filling materials leads to nanocomposites with specific physical properties caused by the nanometric size and give rise to a multiplicity of potential applications in spintronics, magnetic and magneto-optic devices, nutritional food additives as well as drug delivery. Full article
(This article belongs to the Special Issue Porous Materials)
Open AccessReview Influence of Chemical Conditions on the Nanoporous Structure of Silicate Aerogels
Materials 2010, 3(1), 704-740; doi:10.3390/ma3010704
Received: 3 November 2009 / Revised: 24 December 2009 / Accepted: 20 January 2010 / Published: 26 January 2010
Cited by 36 | PDF Full-text (932 KB) | HTML Full-text | XML Full-text
Abstract
Silica or various silicate aerogels can be characterized by highly porous, open cell, low density structures. The synthesis parameters influence the three-dimensional porous structures by modifying the kinetics and mechanism of hydrolysis and condensation processes. Numerous investigations have shown that the structure of
[...] Read more.
Silica or various silicate aerogels can be characterized by highly porous, open cell, low density structures. The synthesis parameters influence the three-dimensional porous structures by modifying the kinetics and mechanism of hydrolysis and condensation processes. Numerous investigations have shown that the structure of porous materials can be tailored by variations in synthesis conditions (e.g., the type of precursors, catalyst, and surfactants; the ratio of water/precursor; the concentrations; the medium pH; and the solvent). The objectives of this review are to summarize and elucidate the effects of chemical conditions on the nanoporous structure of sol-gel derived silicate aerogels. Full article
(This article belongs to the Special Issue Porous Materials)
Open AccessReview Porous Dielectrics in Microelectronic Wiring Applications
Materials 2010, 3(1), 536-562; doi:10.3390/ma3010536
Received: 7 December 2009 / Revised: 1 January 2010 / Accepted: 14 January 2010 / Published: 18 January 2010
Cited by 22 | PDF Full-text (349 KB) | HTML Full-text | XML Full-text
Abstract
Porous insulators are utilized in the wiring structure of microelectronic devices as a means of reducing, through low dielectric permittivity, power consumption and signal delay in integrated circuits. They are typically based on low density modifications of amorphous SiO2 known as SiCOH
[...] Read more.
Porous insulators are utilized in the wiring structure of microelectronic devices as a means of reducing, through low dielectric permittivity, power consumption and signal delay in integrated circuits. They are typically based on low density modifications of amorphous SiO2 known as SiCOH or carbon-doped oxides, in which free volume is created through the removal of labile organic phases. Porous dielectrics pose a number of technological challenges related to chemical and mechanical stability, particularly in regard to semiconductor processing methods. This review discusses porous dielectric film preparation techniques, key issues encountered, and mitigation strategies. Full article
(This article belongs to the Special Issue Porous Materials)
Figures

Open AccessReview A New Approach to the Computer Modeling of Amorphous Nanoporous Structures of Semiconducting and Metallic Materials: A Review
Materials 2010, 3(1), 467-502; doi:10.3390/ma3010467
Received: 8 November 2009 / Revised: 20 December 2009 / Accepted: 11 January 2010 / Published: 15 January 2010
Cited by 7 | PDF Full-text (3696 KB) | HTML Full-text | XML Full-text
Abstract
We review our approach to the generation of nanoporous materials, both semiconducting and metallic, which leads to the existence of nanopores within the bulk structure. This method, which we have named as the expanding lattice method, is a novel transferable approach which consists
[...] Read more.
We review our approach to the generation of nanoporous materials, both semiconducting and metallic, which leads to the existence of nanopores within the bulk structure. This method, which we have named as the expanding lattice method, is a novel transferable approach which consists first of constructing crystalline supercells with a large number of atoms and a density close to the real value and then lowering the density by increasing the volume. The resulting supercells are subjected to either ab initio or parameterized—Tersoff-based—molecular dynamics processes at various temperatures, all below the corresponding bulk melting points, followed by geometry relaxations. The resulting samples are essentially amorphous and display pores along some of the “crystallographic” directions without the need of incorporating ad hoc semiconducting atomic structural elements such as graphene-like sheets and/or chain-like patterns (reconstructive simulations) or of reproducing the experimental processes (mimetic simulations). We report radial (pair) distribution functions, nanoporous structures of C and Si, and some computational predictions for their vibrational density of states. We present numerical estimates and discuss possible applications of semiconducting materials for hydrogen storage in potential fuel tanks. Nanopore structures for metallic elements like Al and Au also obtained through the expanding lattice method are reported. Full article
(This article belongs to the Special Issue Porous Materials)
Open AccessReview Recent Developments in Carbon Nanotube Membranes for Water Purification and Gas Separation
Materials 2010, 3(1), 127-149; doi:10.3390/ma3010127
Received: 17 November 2009 / Revised: 23 December 2009 / Accepted: 24 December 2009 / Published: 4 January 2010
Cited by 85 | PDF Full-text (2881 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Carbon nanotubes (CNTs) are nanoscale cylinders of graphene with exceptional properties such as high mechanical strength, high aspect ratio and large specific surface area. To exploit these properties for membranes, macroscopic structures need to be designed with controlled porosity and pore size. This
[...] Read more.
Carbon nanotubes (CNTs) are nanoscale cylinders of graphene with exceptional properties such as high mechanical strength, high aspect ratio and large specific surface area. To exploit these properties for membranes, macroscopic structures need to be designed with controlled porosity and pore size. This manuscript reviews recent progress on two such structures: (i) CNT Bucky-papers, a non-woven, paper like structure of randomly entangled CNTs, and (ii) isoporous CNT membranes, where the hollow CNT interior acts as a membrane pore. The construction of these two types of membranes will be discussed, characterization and permeance results compared, and some promising applications presented. Full article
(This article belongs to the Special Issue Porous Materials)
Figures

Open AccessReview Macroporous Monolithic Polymers: Preparation and Applications
Materials 2009, 2(4), 2429-2466; doi:10.3390/ma2042429
Received: 9 November 2009 / Revised: 8 December 2009 / Accepted: 14 December 2009 / Published: 18 December 2009
Cited by 21 | PDF Full-text (635 KB) | HTML Full-text | XML Full-text
Abstract
In the last years, macroporous monolithic materials have been introduced as a new and useful generation of polymers used in different fields. These polymers may be prepared in a simple way from a homogenous mixture into a mold and contain large interconnected pores
[...] Read more.
In the last years, macroporous monolithic materials have been introduced as a new and useful generation of polymers used in different fields. These polymers may be prepared in a simple way from a homogenous mixture into a mold and contain large interconnected pores or channels allowing for high flow rates at moderate pressures. Due to their porous characteristics, they could be used in different processes, such as stationary phases for different types of chromatography, high-throughput bioreactors and in microfluidic chip applications. This review reports the contributions of several groups working in the preparation of different macroporous monoliths and their modification by immobilization of specific ligands on the products for specific purposes. Full article
(This article belongs to the Special Issue Porous Materials)
Figures

Open AccessReview Surface Chemistry in Nanoscale Materials
Materials 2009, 2(4), 2404-2428; doi:10.3390/ma2042404
Received: 31 October 2009 / Revised: 5 December 2009 / Accepted: 14 December 2009 / Published: 16 December 2009
Cited by 18 | PDF Full-text (1274 KB) | HTML Full-text | XML Full-text
Abstract
Although surfaces or, more precisely, the surface atomic and electronic structure, determine the way materials interact with their environment, the influence of surface chemistry on the bulk of the material is generally considered to be small. However, in the case of high surface
[...] Read more.
Although surfaces or, more precisely, the surface atomic and electronic structure, determine the way materials interact with their environment, the influence of surface chemistry on the bulk of the material is generally considered to be small. However, in the case of high surface area materials such as nanoporous solids, surface properties can start to dominate the overall material behavior. This allows one to create new materials with physical and chemical properties that are no longer determined by the bulk material, but by their nanoscale architectures. Here, we discuss several examples, ranging from nanoporous gold to surface engineered carbon aerogels that demonstrate the tuneability of nanoporous solids for sustainable energy applications. Full article
(This article belongs to the Special Issue Porous Materials)
Open AccessReview Silk Fibroin Based Porous Materials
Materials 2009, 2(4), 2276-2295; doi:10.3390/ma2042276
Received: 28 October 2009 / Revised: 1 December 2009 / Accepted: 7 December 2009 / Published: 9 December 2009
Cited by 33 | PDF Full-text (229 KB) | HTML Full-text | XML Full-text
Abstract
Silk from the Bombyx mori silkworm is a protein-based fiber. Bombyx mori silk fibroin (SF) is one of the most important candidates for biomedical porous material based on its superior machinability, biocompatibility, biodegradation, bioresorbability, and so on. In this paper, we have reviewed
[...] Read more.
Silk from the Bombyx mori silkworm is a protein-based fiber. Bombyx mori silk fibroin (SF) is one of the most important candidates for biomedical porous material based on its superior machinability, biocompatibility, biodegradation, bioresorbability, and so on. In this paper, we have reviewed the key features of SF. Moreover we have focused on the morphous, technical processing, and biocompatibility of SF porous materials, followed by the application research. Finally, we provide a perspective the potential and problems of SF porous materials. Full article
(This article belongs to the Special Issue Porous Materials)
Open AccessReview Nanoporous Gold: Fabrication, Characterization, and Applications
Materials 2009, 2(4), 2188-2215; doi:10.3390/ma2042188
Received: 27 October 2009 / Revised: 29 November 2009 / Accepted: 2 December 2009 / Published: 3 December 2009
Cited by 78 | PDF Full-text (2295 KB) | HTML Full-text | XML Full-text
Abstract
Nanoporous gold (np-Au) has intriguing material properties that offer potential benefits for many applications due to its high specific surface area, well-characterized thiol-gold surface chemistry, high electrical conductivity, and reduced stiffness. The research on np-Au has taken place on various fronts, including advanced
[...] Read more.
Nanoporous gold (np-Au) has intriguing material properties that offer potential benefits for many applications due to its high specific surface area, well-characterized thiol-gold surface chemistry, high electrical conductivity, and reduced stiffness. The research on np-Au has taken place on various fronts, including advanced microfabrication and characterization techniques to probe unusual nanoscale properties and applications spanning from fuel cells to electrochemical sensors. Here, we provide a review of the recent advances in np-Au research, with special emphasis on microfabrication and characterization techniques. We conclude the paper with a brief outline of challenges to overcome in the study of nanoporous metals. Full article
(This article belongs to the Special Issue Porous Materials)
Figures

Open AccessReview Modelling of Grain Growth Kinetics in Porous Ceramic Materials under Normal and Irradiation Conditions
Materials 2009, 2(3), 1252-1287; doi:10.3390/ma2031252
Received: 10 July 2009 / Revised: 28 August 2009 / Accepted: 2 September 2009 / Published: 10 September 2009
Cited by 7 | PDF Full-text (501 KB) | HTML Full-text | XML Full-text
Abstract
Effect of porosity on grain growth is both the most frequent and technologically important situation encountered in ceramic materials. Generally this effect occurs during sintering, however, for nuclear fuels it also becomes very important under reactor irradiation conditions. In these cases pores and
[...] Read more.
Effect of porosity on grain growth is both the most frequent and technologically important situation encountered in ceramic materials. Generally this effect occurs during sintering, however, for nuclear fuels it also becomes very important under reactor irradiation conditions. In these cases pores and gas bubbles attached to the grain boundaries migrate along with the boundaries, in some circumstances giving a boundary migration controlled by the movement, coalescence and/or sintering of these particles. New mechanisms of intergranular bubble and pore migration which control the mobility of the grain boundary under normal and irradiation conditions are reviewed in this paper. Full article
(This article belongs to the Special Issue Porous Materials)

Journal Contact

MDPI AG
Materials Editorial Office
St. Alban-Anlage 66, 4052 Basel, Switzerland
materials@mdpi.com
Tel. +41 61 683 77 34
Fax: +41 61 302 89 18
Editorial Board
Contact Details Submit to Materials
Back to Top