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8 páginas, 8 figuras. ; Aromatic, triphenylphosphine-containing organometallic compounds, as well as non-aromatic organometallic targets, were irradiated with a Nd:YAG laser to study the role of the metals and ligands used on the structure of the resulting materials. Characterization shows that the composition, metal nanoparticle dilution and crystallite size, and structure of the carbon foams (CFs) produced can be tailored by choosing the metals and ligands of the irradiated targets. The results indicate that precursors containing triphenylphosphine ligands tend to yield larger amounts of ablation products in which graphitic structures are observed in appreciably larger quantities. Electron microscopy reveals that these CFs are multi-component materials that consist of metal nanoparticles embedded in amorphous carbon aggregates, amorphous carbon nanoparticles, and graphitic nanostructures, which can be eventually observed as independent, separate components in the produced soots. The graphitic structures observed can also be produced by laser ablation of triphenylphosphine, indicating that their growth is not promoted by the metals of the chosen aromatic organometallic compounds. ; This work has been supported by the regional Government of Aragón (Spain, Projects PM028/2007 and PI119/09, and Excellence Research Groups funding), MICINN (Spain, Projects TEC2004-05098-C02-02, CTQ2008-06716-C03-01, MAT2004- 01248, MAT2007-64486-C07-02, CEN-20072014), CSIC (Spain, Program I3 2006 8 0I 060), and the European Regional Development Fund (ERDF). ; Peer reviewed

This document is the Accepted Manuscript version of a Published Work that appeared in final form in Journal of the American Chemical Society, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/jacs.9b12389 ; Covalent organic frameworks (COFs) are commonly synthesized under harsh conditions yielding unprocessable powders. Control in their crystallization process and growth has been limited to studies conducted in hazardous organic solvents. Herein, we report a one-pot synthetic method that yields stable aqueous colloidal solutions of sub-20 nm crystalline imine-based COF particles at room temperature and ambient pressure. Additionally, through the combination of experimental and computational studies, we investigated the mechanisms and forces underlying the formation of such imine-based COF colloids in water. Further, we show that our method can be used to process the colloidal solution into 2D and 3D COF shapes as well as to generate a COF ink that can be directly printed onto surfaces. These findings should open new vistas in COF chemistry, enabling new application areas ; This work was supported by the European Union (ERC-2015-STG microCrysFact 677020), the Swiss National Science Foundation (Project No. 200021_181988), ETH Zürich and Ministry of Science, Innovation and Universities MICINN (MAT2016-77608-C3-1P). R.P. acknowledges the Spanish MINECO (Grant No. CTQ2017—88948-P). A.E.P.P. acknowledges a TALENTO grant (2017-T1/IND5148) from Comunidad de Madrid. I.S. acknowledges the Ministry of Human Capacities of Hungary (20391-/2018/FEKUSTRAT). G.M.P. acknowledges the funding received by the Swiss National Science Foundation (SNSF grant number 200021_175735) and by the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement No. 818776 - DYNAPOL). D.M. acknowledges financial support from the European Union (ERC-Co 615954). ICN2 is supported by the Severo Ochoa program from the Spanish MINECO (Grant No. SEV-2017-0706). S.P. acknowledges funding from a Consolidator Grant from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (Grant Agreement No. 771565). We acknowledge DESY (Hamburg, Germany), a member of the Helmholtz Association HGF, for the provision of experimental facilities. Synchrotron X-ray diffraction experiments with COF-TAPB-BTCA were carried out at the beamline P02.1 PETRA III under the proposal I-20170717 EC. We acknowledge Jaume Caelles for SAXS/WAXS measurements performed at IQAC–CSIC.

Covalent organic frameworks (COFs) are commonly synthesized under harsh conditions yielding unprocessable powders. Control in their crystallization process and growth has been limited to studies conducted in hazardous organic solvents. Herein, we report a one-pot synthetic method that yields stable aqueous colloidal solutions of sub-20 nm crystalline imine-based COF particles at room temperature and ambient pressure. Additionally, through the combination of experimental and computational studies, we investigated the mechanisms and forces underlying the formation of such imine-based COF colloids in water. Further, we show that our method can be used to process the colloidal solution into 2D and 3D COF shapes as well as to generate a COF ink that can be directly printed onto surfaces. These findings should open new vistas in COF chemistry, enabling new application areas. ; This work was supported by the European Union (ERC-2015-STG microCrysFact 677020), the Swiss National Science Foundation (Project No. 200021_181988), ETH Zürich and Ministry of Science, Innovation and Universities MICINN (MAT2016-77608-C3-1P). R.P. acknowledges the Spanish MINECO (Grant No. CTQ2017—88948-P). A.E.P.P. acknowledges a TALENTO grant (2017-T1/IND5148) from Comunidad de Madrid. I.S. acknowledges the Ministry of Human Capacities of Hungary (20391-/2018/FEKUSTRAT). G.M.P. acknowledges the funding received by the Swiss National Science Foundation (SNSF grant number 200021_175735) and by the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement No. 818776 - DYNAPOL). D.M. acknowledges financial support from the European Union (ERC-Co 615954). ICN2 is supported by the Severo Ochoa program from the Spanish MINECO (Grant No. SEV-2017-0706). S.P. acknowledges funding from a Consolidator Grant from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (Grant Agreement No. 771565). We acknowledge DESY (Hamburg, Germany), a member of the Helmholtz Association HGF, for the provision of experimental facilities. Synchrotron X-ray diffraction experiments with COF-TAPB-BTCA were carried out at the beamline P02.1 PETRA III under the proposal I-20170717 EC. We acknowledge Jaume Caelles for SAXS/WAXS measurements performed at IQAC–CSIC. ; Peer reviewed