Río, Juan Ignacio delJuan Ignacio delRíoJuhász, LauraLauraJuhászKalmár, JózsefJózsefKalmárErdélyi, ZoltánZoltánErdélyiBermejo, María DoloresMaría DoloresBermejoMartín, ÁngelÁngelMartínSmirnova, IrinaIrinaSmirnovaGurikov, PavelPavelGurikovSchröter, BaldurBaldurSchröter2023-10-202023-10-202023Nanoscale Advances 5: 6635–6646 (2023)https://hdl.handle.net/11420/43713In the present work, a series of metal nanoparticle-decorated carbogels (M-DCs) was synthesized starting from beads of parent metal-crosslinked alginate aerogels (M-CAs), comprising Ca(II), Ni(II), Cu(II), Pd(II) and Pt(lV) ions, followed by pyrolysis under N2 atmosphere up to pyrolysis temperatures of TP = 600 ºC. The textural properties of M-CAs are found to depend on the crosslinking ion, yielding fibrous pore networks with high specific mesoporous volume and specific surface area SV (SV ~ 480 – 687 m2/g) for M-CAs crosslinked with hard cations, Ca(II), Ni(II) and Cu(II), and comparably loose networks with increased macroporosity and lower specific surface (SV ~ 240 – 270 m2/g) for Pd(II) and Pt(IV) crosslinked aerogels. The pyrolysis of M-CAs resulted in two simultaneously occurring processes: changes of the solid backbone and the growth of metal/metal oxide nanoparticles (NPs). The thermogravimetric analysis (TGA) showed a significant influence of the crosslinking cation on the decomposition mechanism and associated change of textural properties. Backscattered electron scanning electron microscopy imaging (SEM-BSE) and X-ray diffraction revealed that metal ions (molecularly dispersed in the parent aerogels) formed nanoparticles composed of elementary metals and metal oxides in varying ratios over the course of pyrolytic treatment. Increasing the TP led to in generally larger nanoparticles. The pyrolysis of the nickel-crosslinked aerogel (Ni-CA) preserved to a large extent the mesoporous structure and resulted in the evolution of fine (~ 14 nm) homogeneously dispersed Ni/NiO nanoparticles. Overall, this work presents a green approach for synthesizing metal-nanoparticle containing carbon materials, useful in emerging technologies related to heterogeneous catalysis, electrocatalysis among others.en2516-0230202366356646Royal Society of Chemistryhttps://creativecommons.org/licenses/by-nc/4.0/aerogelsalginate crosslinkingcarbogelsgreen chemistrymetallic-clusters evolutionpyrolysis treatmentChemistryJournal Article10.15480/882.872610.1039/D3NA00444A10.15480/882.8726Journal Article