Ultra-micropore AnalysisThe term ultra-micropore, sometimes also super-micropore, has become commonly used to describe pores smaller than 1nm diameter (micropores in general are those smaller than 2nm diameter). Ultra-micropores are commonly present in materials such as activated carbons, carbon nanotubes, zeolites, metal organic frameworks (MOFs), zeolitic imidazolate frameworks (ZIFs) and covalent organic frameworks (COFs). Their presence is often fundamental to applications and can be extremely influential to capacity, activity, adsorption behaviour, functionality and accessibility. Typical applications include battery materials, adsorbents and filters, catalysts and gas storage / sequestration materials. Whilst micropores are frequently required, their specific size and volume must be tightly controlled in order to maximise performance characteristics. Micropores of the wrong size may cause poor performance or product failure due to low capacity, inaccessibility or pore blocking.Using the most recent, state-of-the-art instrumentation it is possible to fully characterise micropores for their volume, surface area and size distribution. Together these describe the porous nature of a material and allow for the relationships with material selection and performance to be established. It is then possible to define the specific porous characteristics required from material selection, design, production or regeneration.
Key ApplicationsMicropore size distribution, volume and pore area for:Adsorbent capacity, accessibility and retentionSequestration capacity, accessibility and retentionGas storage capacity, accessibility and retentionCatalyst efficiency and activity Battery electrode efficiency, activity and charge / discharge abilityFilter efficiency and efficacyDetermination of regeneration conditions and efficiencyInvestigations of atypical performance: effects of low capacity and retentionInvestigations of product failure: pore blockingIdentification of optimum characteristics and selection of materials Determination of production and fabrication conditions
At MCA Services we use the latest, state-of-the-art Micromeritics 3Flex instrument for micropore analysis which applies the volumetric method for the measurement of adsorption isotherms. Nitrogen is most commonly used as the adsorbate with excellent results and the capability of extending analyses to measure data in the mesopore region. Combined micropore and mesopore analyses are, therefore, possible in a single analysis and extensive data reduction and reporting methods can be employed to characterise each. With some sample materials, when unfavourable interactions between nitrogen and the sample surface are area likely, it is preferable to select an alternative adsorbate. In such cases argon adsorption is a suitable analytical method. However, when samples contain ultra-micropores smaller than approximately 0.5nm, nitrogen and argon adsorption become problematic due to slow or incomplete accessibility to the smallest pores at the analysis temperature. In such cases, CO2adsorption is recommended as this can be used to characterise pores as in the range 0.32 - 1.0 nm diameter (depending on analysis temperature). It is also possible to combine CO2adsorption isotherms with those of N2 or Ar to obtain a complete pore characterisation throughout the micropore and mesopore ranges.
Analytical Options and HighlightsNitrogen adsorption isotherms for micropore and mesopore characterisationArgon adsorption isotherms for micropore and mesopore characterisationCarbon dioxide adsorption isotherms for ultra- micropore characterisationNitrogen adsorption at 77KArgon adsorption at 77K or 87KCarbon dioxide adsorption at 258 – 298 KMicropore size distribution data (graphical and numerical)Micropore volume and surface area data (graphical and numerical)Combination of CO2 and N2 or Ar data for complete characterisationData reduction by DFT and NL-DFT methodsComprehensive degassing options
The Micromeritics 3Flex is an extremely powerful instrument with cutting edge technology and a wealth of information can be obtained from comprehensive data reduction software. Combined with our decades of experience the maximum information about your samples can be obtained from a single analysis. At MCA Services we are always happy to advise the best analytical option for your particular samples, applications and requirements. We also routinely assist in data interpretation: selecting the most pertinent reporting data and relating porous characteristics to your specific materials and requirements.
MCA Services
01763 262333
Ultra-micropore AnalysisThe term ultra-micropore, sometimes also super-micropore, has become commonly used to describe pores smaller than 1nm diameter (micropores in general are those smaller than 2nm diameter). Ultra-micropores are commonly present in materials such as activated carbons, carbon nanotubes, zeolites, metal organic frameworks (MOFs), zeolitic imidazolate frameworks (ZIFs) and covalent organic frameworks (COFs). Their presence is often fundamental to applications and can be extremely influential to capacity, activity, adsorption behaviour, functionality and accessibility. Typical applications include battery materials, adsorbents and filters, catalysts and gas storage / sequestration materials. Whilst micropores are frequently required, their specific size and volume must be tightly controlled in order to maximise performance characteristics. Micropores of the wrong size may cause poor performance or product failure due to low capacity, inaccessibility or pore blocking.Using the most recent, state-of-the-art instrumentation it is possible to fully characterise micropores for their volume, surface area and size distribution. Together these describe the porous nature of a material and allow for the relationships with material selection and performance to be established. It is then possible to define the specific porous characteristics required from material selection, design, production or regeneration.
Key Applications Micropore size distribution, volume and pore area for:Adsorbent capacity, accessibility and retentionSequestration capacity, accessibility and retentionGas storage capacity, accessibility and retentionCatalyst efficiency and activity Battery efficiency, activity and charge / discharge abilityFilter efficiency and efficacyDetermination of regeneration conditions and efficiencyInvestigations of atypical performance: effects of low capacity and retentionInvestigations of product failure: pore blockingIdentification of optimum characteristics and materials selection Determination of production and fabrication conditions
At MCA Services we use the latest, state-of-the-art Micromeritics 3Flex instrument for micropore analysis which applies the volumetric method for the measurement of adsorption isotherms. Nitrogen is most commonly used as the adsorbate with excellent results and the capability of extending analyses to measure data in the mesopore region. Combined micropore and mesopore analyses are, therefore, possible in a single analysis and extensive data reduction and reporting methods can be employed to characterise each. With some sample materials, when unfavourable interactions between nitrogen and the sample surface are area likely, it is preferable to select an alternative adsorbate. In such cases argon adsorption is a suitable analytical method. However, when samples contain ultra-micropores smaller than approximately 0.5nm, nitrogen and argon adsorption become problematic due to slow or incomplete accessibility to the smallest pores at the analysis temperature. In such cases, CO2 adsorption is recommended as this can be used to characterise pores as in the range 0.32 - 1.0 nm diameter (depending on analysis temperature). It is also possible to combine CO2 adsorption isotherms with those of N2 or Ar to obtain a complete pore characterisation throughout the micropore and mesopore ranges.
Analytical Options and Highlights Nitrogen adsorption for micropore and mesopore characterisationArgon adsorption for micropore and mesopore characterisationCarbon dioxide isotherms for ultra- micropore characterisationNitrogen adsorption at 77KArgon adsorption at 77K or 87KCarbon dioxide adsorption at 258 – 298 KMicropore size distribution data (graphical and numerical)Micropore volume and surface area data Combination of CO2 and N2 or Ar data Data reduction by DFT and NL-DFT methodsComprehensive degassing options
The Micromeritics 3Flex is an extremely powerful instrument with cutting edge technology and a wealth of information can be obtained from comprehensive data reduction software. Combined with our decades of experience the maximum information about your samples can be obtained from a single analysis. At MCA Services we are always happy to advise the best analytical option for your particular samples, applications and requirements. We also routinely assist in data interpretation: selecting the most pertinent reporting data and relating porous characteristics to your specific materials and requirements.