Résumé
In the past few years, 3D printing has gained a lot of interest in material chemistry, giving access to highly complex structures that could not be produced using conventional approaches. Among 3D printing techniques, digital light processing (DLP) allows for the rapid printing of monolithic structures with high freedom of design and high accuracy until a 10 m resolution (Fig. 1a). Printed structures can be tailored to address specific needs, for instance through the implementation of complex and well controlled macropore networks. In parallel, zeolites have outstanding specific properties for many applications (catalysis, adsorption) due to their controlled microporosity. The combination of 3D printing with zeolites would hence generate important opportunities for the manufacturing of hierarchically porous zeolites monoliths for process intensification.Here, we introduce a novel pathway for the fabrication of 3D zeolite monoliths through the pseudomorphic transformation of DLP printed mesoporous silica structures. These monoliths are first printed from inks made of mesoporous silica nanocages functionalized with photosensitive ligands[1]. In contrast to common nanocomposite approaches, these inks do not require any resin or binder. The resulting silica monoliths have very low organic fractions and can be directly converted into zeolites without any calcination step (Fig. 1b). The 3D silica monoliths are then converted into 3D LTA or LTA/FAU-X monoliths (Fig. 1c,d) by pseudomorphic transformation[2,3]. In future, this process could be extended to a large variety of complex 3D macroporous structures as gyroids and to other type of zeolites. References[1] T. Aubert, J. Huang, K. Ma, T. Hanrath, U. Wiesner, Porous cage-derived nanomaterial inks for direct and internal three-dimensional printing, Nature Communications, 11 (2020) 4695.[2] B. Said, T. Cacciaguerra, F. Tancret, F. Fajula, A. Galarneau, Size control of self-supported LTA zeolite nanoparticles monoliths, Microporous and Mesoporous Materials, 227 (2016) 176.[3] Y. Didi, B. Said, et al., Synthesis of binderless FAU-X (13X) monoliths with hierarchical porosity, Microporous and Mesoporous Materials, 281 (2019) 57