Pore structure of silica gel: a comparative study through BET and PALS

Porous nature of silica gel samples comprising of micro- and meso-pores were studied with the help of positron annihilation lifetime spectroscopy based on a simple and realistic model which was further compared by nitrogen gas adsorption method namely Brunauer, Emmett and Teller isotherm. The final results illustrate the merits and fineness of the former, the extent of corroboration of the results and also the discrepancies accruing due to the limitations of the latter.