BET Characterization of Specific Surface Area, Pore Size, Porosity Analytical Service

Our BET characterization services are designed to quickly and accurately analyze the surface area, pore size and porosity of a sample. Designed for reliable accuracy, our advanced technology and rigorous QA/QC protocols ensure results to be high quality. Reduce research time and maximize efficiency with our trusted analytical services.

MSE Analytical Services offer professional BET Surface Area, Pore Size, Porosity Characterization Service using Quantachrome SI or Micromeritics ASAP 2460.

Analytical Service Minimum order requirement: $250 per order. A $200 handling fee will be applied if order is below $250.

* Note: Data analysis service is not included in the list prices.

Highlights: High Quality Data, Competitive Pricing, Technical Support by Scientists.

The BET (Brunauer, Emmett and Teller) theory is commonly used to evaluate the gas adsorption data and generate a specific surface area result expressed in units of area per mass of sample (m2/g). The technique is referenced by several standard organizations such as ISO, USP and ASTM.

This method is widely used for most materials, but is most reliable for materials with a Type II or Type IV isotherm with sufficient level of interaction between the adsorbate gas and the surface. For materials with other types of isotherms, the BET theory may not apply for various reasons and therefore should be treated with caution.

Prior to analysis, the sample must be preconditioned to remove physically bonded impurities from the surface of the powder in a process called degassing or outgassing. This is typically accomplished by applying elevated temperature to the sample in conjunction with vacuum or continuously flowing inert gas. This process must be carefully controlled and monitored in order to generate the most accurate and repeatable results.

The specific surface area of a material is then determined by the physical adsorption of a gas (typically nitrogen, krypton, or argon) onto the surface of the sample at cryogenic temperatures (typically liquid nitrogen or liquid argon temperatures). The choice of gas to be used is dependent on the expected surface area and the properties of the sample. Once the amount of adsorbate gas has been measured (either by a volumetric or continuous flow technique), calculations which assume a monomolecular layer of the known gas are applied. BET surface area analysis must be done in the linear region of the BET plot, which could be systematically evaluated using the Rouquerol transform. Contact us today for BET porosity, pore size, and surface area analysis.

Reservation Instructions

1. For Nitrogen Adsorption Testing, the Sample Requirements Are as Follows (Results Accuracy Cannot Be Guaranteed If Insufficient Sample Quantity Is Provided):

(1) If there is a rough estimate of the specific surface area (SSA): you can use the formula: Specific Surface Area (m²/g) × Sample Mass (g) = 15–20 m² to approximate the required sample amount. The testing technician will determine the actual sample quantity based on the situation. For samples with SSA greater than 400 m²/g, it is recommended to provide no less than 50 mg to reduce weighing errors. When booking, please specify the expected SSA range. If the results are inaccurate due to insufficient sample quantity, re-testing is generally not arranged.

(2) For SSA < 10 m²/g:
It is recommended to provide a sample volume of 6–8 mL. For SSA < 100 m²/g, it is recommended to provide 1–2 g of the sample. For samples prone to sticking to the tube walls, being very lightweight, or having static electricity, sample losses may occur during weighing. In such cases, it is recommended to provide extra sample amounts.

(3) If the SSA is unknown:

• For total pore and micropore mode, the sample mass generally needs to exceed 100 mg (assuming micropores are present).
• For mesopore mode, at least 250 mg is required.

2. General Sample Preparation Guidelines:
Samples are usually in powder form. If the sample is granular, it should be physically crushed to a particle size of less than 3 mm, with the total mass meeting the quantity requirements mentioned in 1. To facilitate sampling, please avoid using resealable bags for packaging.

3. Degassing Temperature Requirements:
The degassing temperature must fall within the sample's stability range and should not exceed half of its melting point temperature! The actual vacuum degassing temperature is higher than in an oven. If the sample is prone to decomposition or explosion during heating, please inform in advance. Otherwise, you will bear responsibility for any subsequent issues.

4. Pore Size Ranges:

• Mesopores: Suitable pore diameter range: 2 nm ≤ φ ≤ 50 nm
• Total pores: Suitable pore diameter range: 0.3–50 nm
• Note: BET data cannot directly provide porosity information.

5. Recovery Risk Notice:
There is a risk of sample loss during BET testing due to high-temperature degassing or sample adherence to tube walls, and 100% recovery cannot be guaranteed. If the sample does not react with absolute ethanol, you can indicate a preference to rinse the sample tube with absolute ethanol for recovery.

Please contact sales@msesupplies.com for additional information and instructions on our Analytical Services program. Confirmation of the sample(s) requirements, SDS sheets and additional information is needed prior to processing the Analytical Service order. 

***Please do not ship any samples without authorization from MSE Supplies***