Search

The use of covalent organic frameworks (COFs) in practical applications demands shaping them into macroscopic objects, which remains challenging. Herein, we report a simple three-step method to produce COF aerogels, based on sol-gel transition, solvent-exchange, and supercritical CO drying, in which 2D imine-based COF sheets link together to form hierarchical porous structures. The resultant COF aerogel monoliths have extremely low densities (ca. 0.02 g cm), high porosity (total porosity values of ca. 99 %), and mechanically behave as elastic materials under a moderate strain (, This work has been supported by the Spanish MINECO (PID2019-106268GB-C32, MAT2016-77608-C3-1-P, PCI2018-093081, PID2019-108028GB-C21, and RTI2018-095622-B-I00), the Catalan AGAUR (project 2017 SGR 238), Basque Government (IT1291-19), and through the “María de Maeztu” Programme for Units of Excellence in R&D (CEX2018-000805-M). It was also funded by the CERCA Program/Generalitat de Catalunya. ICN2 is supported by the Severo Ochoa program from the Spanish MINECO (Grant No. SEV-2017-0706).

This is the peer reviewed version of the following article: Rodríguez‐San‐Miguel, D., Yazdi, A., Guillerm, V., Pérez‐Carvajal, J., Puntes, V., Maspoch, D., & Zamora, F. (2017). Confining Functional Nanoparticles into Colloidal Imine‐Based COF Spheres by a Sequential Encapsulation–Crystallization Method. Chemistry–A European Journal, 23(36), 8623-8627, which has been published in final form at https://doi.org/10.1002/chem.201702072. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions, Here, a two-step method is reported that enables imparting new functionalities to covalent organic frameworks (COFs) by nanoparticle confinement. The direct reaction between 1,3,5-tris(4-aminophenyl)benzene and 1,3,5-benzenetricarbaldehyde in the presence of a variety of metallic/metal-oxide nanoparticles resulted in embedding of the nanoparticles in amorphous and non-porous imine-linked polymer organic spheres (NP@a-1). Post-treatment reactions of NP@a-1 with acetic acid under reflux led to crystalline and porous imine-based COF-hybrid spheres (NP@c-1). Interestingly, Au@c-1 and Pd@c-1 were found to be catalytically active, This work was supported by the Spanish MINECO (projects PN MAT2016‐77608‐C3‐1‐P and MAT2015‐65354‐C2‐1‐R), the Catalan AGAUR (project 2014 SGR 80), and the ERC under the EU FP7 (ERC‐Co 615954). V.G. is grateful to the Generalitat de Catalunya for a Beatriu de Pinós fellowship (2014 BP‐B 00155). A.Y. and ICN2 acknowledge the support of the Spanish MINECO through the Severo Ochoa Centers of Excellence Program, under Grant SEV‐2013‐0295

To date, crystallization studies conducted in space laboratories, which are prohibitively costly and unsuitable to most research laboratories, have shown the valuable effects of microgravity during crystal growth and morphogenesis. Herein, an easy and highly efficient method is shown to achieve space-like experimentation conditions on Earth employing custom-made microfluidic devices to fabricate 2D porous crystalline molecular frameworks. It is confirmed that experimentation under these simulated microgravity conditions has unprecedented effects on the orientation, compactness and crack-free generation of 2D porous crystalline molecular frameworks as well as in their integration and crystal morphogenesis. It is believed that this work will provide a new "playground" to chemists, physicists, and materials scientists that desire to process unprecedented 2D functional materials and devices., Advanced Materials, 33 (30), ISSN:0935-9648, ISSN:1521-4095

Can controlled diffusion of reagents together with micro‐shielding features enable the regioselective localization of different chemical processes? In article number 1903172, Josep Puigmarti‐Luis and co‐workers present a method for the in‐situ fabrication of custom designed surface‐enhanced Raman spectroscopy (SERS) substrates as well as for the selective localization of multiple chemical reactions onto surfaces. [Image: see text]

2D-polymers are still dominated by graphene and closely related materials such as boron nitride, transition metal sulphides and oxides. However, the rational combination of molecules with suitable design is already showing the high potential of chemistry in this new research field. The aim of this feature article is to illustrate, and provide some perspectives, the current state-of-the-art in the field of synthetic 2D-polymers showing different alternatives to prepare this novel type of polymers based on the rational use of chemistry. This review comprises a brief revision of the essential concepts, the strategies of preparation following the two general approaches, bottom-up and top-down, and a revision of the promising seminal properties showed by some of these nanomaterials.