Mesopore Measurement
The characterization of porous materials with mesopores (pore diameters between 2 to 50nm) is most commonly determined by gas physisorption. The fundamental principles and procedures of mesopore measurement are similar to BET surface area analysis using the static volumetric method. First, any excess adsorbed surface contaminants are removed from the sample using vacuum or inert gas flow, typically at elevated temperature. Then a probe gas, most commonly nitrogen, is allowed to adsorb onto and desorb from the surface at cryogenic temperature. Pore size distribution, pore volume, and area can be derived from the adsorption and desorption data using an appropriate mathematical model such as the Barrett-Joyner-Halenda (BJH) theory. This technique is referenced by several standard organizations such as ISO, USP, and ASTM.
The characterization of porous materials with mesopores (pore diameters between 2 to 50nm) is most commonly determined by gas physisorption. The fundamental principles and procedures of mesopore measurement are similar to BET surface area analysis using the static volumetric method. First, any excess adsorbed surface contaminants are removed from the sample using vacuum or inert gas flow, typically at elevated temperature. Then a probe gas, most commonly nitrogen, is allowed to adsorb onto and desorb from the surface at cryogenic temperature. Pore size distribution, pore volume, and area can be derived from the adsorption and desorption data using an appropriate mathematical model such as the Barrett-Joyner-Halenda (BJH) theory. This technique is referenced by several standard organizations such as ISO, USP, and ASTM.
By using gas adsorption to measure the pore size distribution of various materials, PTL has aided clients with determining manufacturing process issues, variations in supplier products, and provided quality control testing to numerous industries.
Advantages
- Multi-point BET specific surface area analysis included with mesopore isotherm analysis
- Nitrogen or Argon available for adsorbate gases
- Several instrument options to ensure best fit for material
Considerations
- Higher resolution 40-point analysis recommended; lower resolution 20-point analysis also offered
- Provides pore size distribution and area measurements in the range of 17 Å to 3000 Å (1.7 nm to 300 nm), though best suited for pores in the 2 to 100 nm range
- Appropriate for dry material only
Sample Requirements
The sample must be a dry solid to be analyzed. Ideal sample amount is 2 to 5 grams. If sample availability is limited, please contact PTL. Smaller sample quantities can often be accommodated depending on sample properties.
For additional questions on your sample needs, please contact us to share specifics about your sample and options for suitable sample quantities.
Detection Range
PTL’s gas adsorption mesopore analyzers can measure pore size distribution and area measurements in the range of 17 Å to 3000 Å (1.7 nm to 300 nm) depending on the adsorbate gas utilized and instrument manufacturer.
Data Reported
Pore size distribution and area – BJH Pore Volume (cm3/g), BJH Average Pore diameter (nm), BET Specific Surface Area (m2/g).
Instrumentation
Particle Technology Labs has some of the top players in the industry, such as Micromeritics and Anton Paar/Quantatec.
Micromeritics Tristar II 3020
3Flex Mesopore-Isotherm
Anton Paar NOVA 800
