Sample container temperature gradient influence on the BET specific surface area

J Colloid Interface Sci. 2005 Mar 15;283(2):605-8. doi: 10.1016/j.jcis.2004.11.023.

Abstract

Differences between BET specific surface area (BET SSA) values exist due to data collected in stainless steel and less thermally conductive sample holders. Not accounting for the temperature gradient along stainless steel sample holders during manometric gas adsorption measurements at cryogenic temperatures leads to errors of up to 3.2% in the BET SSA values with a relative combined standard uncertainty (RCSU) of 0.63%. A unidimensional heat flow model accurately accounts for the temperature gradient, leading to an agreement of 0.16% between the BET SSA values for both sample holder units.