A microporous material is a material containing pores with diameters less than 2 nm. Examples of microporous materials include
zeolite
Zeolites are microporous, crystalline aluminosilicate materials commonly used as commercial adsorbents and catalysts. They mainly consist of silicon, aluminium, oxygen, and have the general formula ・y where is either a metal ion or H+. These p ...
s and
metal-organic frameworks.
Porous materials are classified into several kinds by their size. The recommendations of a panel convened by the
International Union of Pure and Applied Chemistry
The International Union of Pure and Applied Chemistry (IUPAC ) is an international federation of National Adhering Organizations working for the advancement of the chemical sciences, especially by developing nomenclature and terminology. It is ...
(IUPAC) are:
[ See page 1745.]
*Microporous materials have pore diameters of less than 2 nm.
*
Mesoporous material
A mesoporous material (or super nanoporous ) is a nanoporous material containing pores with diameters between 2 and 50 nm, according to IUPAC nomenclature. For comparison, IUPAC defines microporous material as a material having pores smaller ...
s have pore diameters between 2 nm and 50 nm.
*
Macroporous material
In soil, macropores are defined as cavities that are larger than 75 μm. Functionally, pores of this size host preferential soil solution flow and rapid transport of solutes and colloids. Macropores increase the hydraulic conductivity of soi ...
s have pore diameters of greater than 50 nm.
Micropores may be defined differently in other contexts. For example, in the context of porous aggregations such as soil, micropores are defined as cavities with sizes less than 30 μm.
Uses in laboratories
Microporous materials are often used in laboratory environments to facilitate contaminant-free exchange of gases. Mold spores, bacteria, and other airborne contaminants will become trapped, while gases are allowed to pass through the material. This allows for a sterile environment within the contained area.
Other uses
Microporous media are used in large format printing applications, normally with a pigment based ink, to maintain colour balance and life expectancy of the resultant printed image.
Microporous materials are also used as high performance insulation in applications ranging from homes to metal furnaces requiring material that can withstand more than 1000 Celsius.
See also
*
Characterisation of pore space in soil The pore space of soil contains the liquid and gas phases of soil, i.e., everything but the solid phase that contains mainly minerals of varying sizes as well as organic compounds.
In order to understand porosity better a series of equations have ...
*
Nanoporous materials
Nanoporous materials consist of a regular organic or inorganic bulk phase in which a porous structure is present. Nanoporous materials exhibit pore diameters that are most appropriately quantified using units of nanometers. The diameter of pores ...
*
Conjugated microporous polymer Conjugated microporous polymers (CMPs) are a sub-class of porous materials that are related to structures such as zeolites, metal-organic frameworks, and covalent organic frameworks, but are amorphous in nature, rather than crystalline. CMPs are a ...
, a type of microporous material
References
Materials
Porous media
{{materials-stub