Porosity is characterized using techniques such as gas adsorption, mercury intrusion porosimetry, and small-angle X-ray scattering (SAXS). Gas adsorption methods, such as nitrogen adsorption, can provide information on pore size distribution and specific surface area. Mercury intrusion porosimetry involves the intrusion of mercury into the pores under pressure, allowing for the measurement of pore size and volume. SAXS provides information on the internal structure and porosity of nanomaterials at the nanoscale.
