Toward a sustainable preparation of tunable mesoporous silica

Abstract We report how we could circumvent two major drawbacks in the potential scale up synthesis of mesoporous silica via the surfactant-based templating route. First, burning the organic templates to free porosity is costly and not environmental friendly. Most of the mesoporous silica materials show also extremely poor resistance to hydrothermal environments. These drawbacks have certainly contributed to prevent these materials meet practical use, and hampered any possible large-scale manufacturing. Unlike previous reports that claimed that supercritical carbon dioxide (scCO 2 ) was ineffective in removing most of the organic templates, except amines, we describe how the unique synergy we achieved between scCO 2 extraction and our two-step synthesis of mesoporous silica with nonionic templates allowed us to overcome these drawbacks. We conducted different tests, and we report here the preparation of mesoporous materials with tunable pore size between 1 and 10 nm, structure varying from 3D wormhole to hexagonal, and hydrothermal resistance.