Brunauer-Emmett-Teller (BET) Surface Area Analysis and Barrett-Joyner-Halenda (BJH) Pore Size and Volume Analysis
BET analysis provides precise specific surface area evaluation of materials by nitrogen multilayer adsorption measured as a function of relative pressure using a fully automated analyzer. The technique encompasses external area and pore area evaluations to determine the total specific surface area in m2/g, yielding important information in studying the effects of surface porosity and particle size in many applications.
BJH analysis can also be employed to determine pore area and specific pore volume using adsorption and desorption techniques. This technique characterises pore size distribution independent of external area due to particle size of the sample.
- Rapid single point and multipoint specific BET surface area determinations
- Full BET surface area characterization of disperse, nonporous or macroporous materials pore diameter >50nm (type II isotherms) and mesoporous materials with pore diameter between 2 nm and 50 nm (type IV isotherms)
- BET surface area characterization of microporous materials (<2 nm, type I isotherms)
- Pore volume and pore area distributions in the mesopore and macropore ranges using BJH analysis with a full complement of adsorbate thickness models
- BJH adsorption and desorption average pore diameter (4V/A) determinations
Specific surface area determinations measuring the external surface area and open pores of macroporous and mesoporous materials, along with pore volume and area distributions that characterise porosity below the effective range of mercury intrusion porosimetry are techniques that can be especially useful for studies of artificial bone materials, catalysts, particle and gas filtration, fuel cell technology, absorbents, sintering studies, zeolites and reactivity studies of materials among a variety of other applications.
Typical industries using BET and BJH analysis
- Medical devices
- Toothpaste manufacture
- Environmental and filtration
- Dyes, paints and pigments
- Fuel cell technology
BET and BJH analysis - at a glance
- Information: Multipoint & single point specific surface area using BET. Pore volume & area distributions with 4V/A pore diameter determination with BJH using a variety of thickness models
- Sample quantity: Minimum of 0.5g for a single sample run
- Pore diameter limits: >2nm - mesoporous and macroporous materials with some applications to microporous materials (<2nm pore size)
- Data output: Graphical and tabulated data for isotherms, BET transforms, linear and log plots, cumulative, incremental and differential data and single value results