Preliminary results of hydrogen adsorption and SAXS modelling of mesoporous silica: MCM-41

A sample of MCM-41 at 77 K was shown to reversibly absorb 1.6 excess wt% of hydrogen at ∼ 3.5 MPa. Though the excess hydrogen adsorption peaked, the total gravimetric wt% of hydrogen adsorption continued to increase and reached a value of 2.7 wt% by ∼ 4.5 MPa. The correlation function has been used here for the first time in an attempt to determine the average pore size, distance between the pores and an estimate of the wall thickness by modelling the entire small angle X-ray scattering (SAXS) curve of the MCM-41 sample. At this stage of the model development, only a lower limit on the average pore size can be determined.