Digital reconstruction of silica gels based on small angle neutron scattering data

Digitally reconstructed porous domains contain statistical information well beyond the pore level and thus constitute accurate models that can be used to relate the structure of porous solids to their macroscopic properties. In this work, we focus on two different porous silica gels and, based on adsorption and SANS data, propose two different processes for their digital reconstruction. The first gel was formed from a sol in which the primary particles exist as aggregates that give a high porosity open gel structure, which was simulated by a diffusion-limited aggregation procedure. For the second gel the uniform discrete sol particles pack efficiently during gelation and produce a low porosity mesoporous structure, which was reconstructed through a Monte Carlo ballistic sphere deposition procedure. In both cases the reconstructed materials possess similar statistical properties with the original gels and can thus serve as models for the simulation of sorption and transport phenomena.