Claudio Evangelisti

Italian National Research Council | CNR · Institute of Chemistry of Organometallic Compounds ICCOM

Aqueous phase reforming (APR) is a promising method for producing hydrogen from biomass-derived feedstocks. In this study, carbon-supported Pt catalysts containing particles of different sizes (below 3 nm) were deposited on different commercially available carbons (i.e., Vulcan XC72 and Ketjenblack EC-600JD) using the metal vapor synthesis approach...

We describe here the synthesis of ultrasmall Pt nanoparticles (NPs) obtained by a robust and reliable protocol using UV-Vis photoreduction of a platinum salt precursor, under continuous flow conditions. These ligand-free Pt NPs were rapidly dispersed onto a solid support or stabilized towards aggregation as a colloidal solution by the addition of a...

Fuels can be produced from the electrochemical reduction of industrial waste CO2 (e-fuels) using renewable energy and hence are an attractive option for the storage of renewable energy in a chemical form. The energy stored in the e-Fuel may be recovered on-demand using a direct fuel cell thus completing a carbon neutral cycle. Anion exchange membra...

In this work, Ni nanoparticles (NPs), with nominal metallic loading of 20 wt%, were deposited on graphene-based materials (GMs) doped with nitrogen and sulphur, in order to study their electrocatalytic activity towards the oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER) in alkaline medium. Different chemical reducing agents we...

The electrocatalytic hydrogen oxidation (HOR) and evolution (HER) reactions under alkaline conditions are kinetically slow processes even when Pt group metals are employed. This presentation discusses our strategies to improve the activity of non platinum catalysts. For example, to improve the alkaline HOR activity of transition metal nanoparticles...

Anion-exchange membrane fuel cells (AEMFCs) allow for the use of Pt-free or precious group metal (PGM-free) catalysts and for a wider choice of cell and stack materials. Currently, there are still development challenges, such as the need to improve the efficiency of anode catalysts, due to the sluggish hydrogen oxidation reaction (HOR) in alkaline...

Acetone-stabilized Au- and Sn-solvated metal atoms (SMAs) were used as to obtain Au- and AuSn-supported catalysts by simple impregnation on a reducible (TiO2) and a non-reducible (Al2O3) metal-oxide. Their catalytic behaviour was investigated for cyclohexane oxidation to cyclohexanol and cyclohexanone (KA oil), and their morphological and physical...

Ni-based catalysts supported on Mg-Al mixed oxides (Mg(Al)O) have been intensively investigated as catalysts for CH4 reforming processes (i.e., steam reforming (SMR) and dry reforming (DRM)), which are pivotal actors in the expanding H2 economy. In this review, we provide for the first time an in-depth analysis of homo- and bimetallic Ni-based cata...

A simple and reproducible approach for the synthesis of Cu-based heterogeneous catalysts, named flow chemisorption hydrolysis (flow-CH), is reported. The approach, derived from the CH method, allows size-controlled CuO nanoparticles (mean diameter 2.9 nm) to be obtained, that are highly and homogeneously dispersed into hierarchically meso-/macropor...

The development of sustainable electrocatalysts is essential for promoting anion exchange membrane water electrolysis technology (AEMWE). Ni-Mo and MoO2 materials have enhanced alkaline hydrogen evolution reaction (HER) activity. This study...

Ultra‐small gold nanoparticles (UAuNPs) are extremely interesting for applications in nanomedicine thanks to their good stability, biocompatibility, long circulation time and efficient clearance pathways. UAuNPs engineered with glycans (Glyco‐UAuNPs) emerged as excellent platforms for many applications since the multiple copies of glycans can mimic...

Ultra‐small gold nanoparticles (UAuNPs) are extremely interesting for applications in nanomedicine thanks to their good stability, biocompatibility, long circulation time and efficient clearance pathways. UAuNPs engineered with glycans (Glyco‐UAuNPs) emerged as excellent platforms for many applications since the multiple copies of glycans can mimic...

Evidence collected to date by our group has demonstrated that tin(II)-functionalized hydroxyapatites (Sn/HAP) are a newly discovered class of ecofriendly reductive adsorbents for Cr(VI) removal from wastewaters. In this work an upgraded series of Sn/HAP materials assured a maximum removal capacity of ≈ 20 mgCr/g, doubling the previously reported va...

Superparamagnetic iron oxide nanoparticles (SPIONs) coated with glucose (Glc-SPIONs) were prepared by a new approach called Metal Vapor Synthesis (MVS) and their morphological/structural features were investigated by transmission electron microscopy (TEM) and dynamic light scattering. TEM analysis revealed the presence of small roundish crystalline...

Polymer‐supported PdCu alloy nanoparticles with a palladium to copper atom ratio of 1 have been synthesized upon: (i) Coordination of palladium/copper acetate to 2,2’‐bipyridine‐end functionalized poly(lactic acid) (PLA); (ii) Stereocomplexation of PLA‐based macrocomplexes of opposite stereochemistry, and (iii) metal reduction with hydrogen. The ob...

Au-based catalysts have been reported to be active in the cyclohexane oxidation to K-A oil, but they showed some limitiations in terms of productivity, selectivity and required reaction conditions. The possibility to overcome some of these limits has been explored coupling Au with Cu, which can be suitable for undergoing the electron-switch in the...

The ever-increasing demand for metal catalysts on the global market has encouraged the development of new approaches for the synthesis of highly efficient catalysts. Metal and organometallic vapor-based synthesis methods allow exerting a high control over the morphological and structural features of the supported metal active phase leading to a sig...

Heterogeneous catalysis is an essential tool for the development of both emerging and established chemical processes, as well as for their economic and environmental sustainability [...]

Supported catalysts are important tools for developing green-economy-based processes. Palladium nanoparticles (NPs) that are immobilized on two fibers developed as metal scavengers (i.e., Smopex®-234 and Smopex®-111, 1% w/w) have been prepared and tested in copper-free cyclocarbonylative Sonogashira reactions. Their catalytic activity has been comp...

We report on the use of In as an effective H2 production promoter in a Cu/SiO2 catalyst for the steam reforming of methanol. To date, In promotion has been limited to noble metals because of its tendency to “bury” other metals thus compromising the catalytic activity. Here, we prepared a silica-supported Cu-In catalyst via a urea-assisted co-precip...

Palladium nanoparticles stabilized by a sterically demanding secondary diamine ligand have been synthesized by hydrogen reduction of a palladium acetate complex bearing the corresponding diimine ligand. The obtained nanoparticles were used to catalyze the aerobic oxidation of 1,2‐propandiol in n‐hexane, and after their heterogenization onto a high...

Electrocatalytic hydrogen oxidation (HOR) and evolution (HER) reactions under alkaline conditions are kinetically sluggish processes even when Pt catalysts are employed. Despite having markedly slower kinetics, nanostructured nickel catalysts represent a cheaper and more sustainable alternative to benchmark Pt-based systems. Accordingly, researcher...

Nanocomposites comprising magnetic nanoparticles (NPs) embedded in an organic conducting polymer are promising materials that may allow one to exploit synergic effects between the electrically conducting and the magnetically permeable components. Having already shown that magnetite NPs can be conveniently used as a catalyst for the oxidative polyme...

For the first time, the co‐presence in the saponite structure of luminescent EuIII and catalytic NbV metal sites was exploited for the simultaneous detection and catalytic abatement of sulfur‐containing blister chemical warfare agents. Metal centers were introduced in structural positions of the saponite (in the interlayer space or inside the inorg...

We present an ecofriendly hydroxyapatite (HAP) material functionalized with tin (Sn/HAP) for an efficient interfacial reduction of Cr(VI) to Cr(III). Tin was deposited on HAP at different concentrations (from 0.2 to 1.2 mmol/g) using colloidal or clear acid solutions of SnCl2. The morphological and structural properties of fresh and used Sn/HAP sam...

Zr/Si mixed oxides with different amounts of silica (0–50 wt%) were prepared by a simple sol–gel method. These catalysts were tested in a cascade reaction of furfural and 5-hydroxymethyl furfural (HMF) with 2-butanol to form the corresponding alcohols or ethers through a combination of transfer hydrogenation and etherification processes under mild...

Any release of radioactive cesium-137, due to unintentional accidents in nuclear plants, represents a dangerous threat for human health and the environment. Prussian blue has been widely studied and used as an antidote for humans exposed to acute internal contamination by Cs-137, due to its ability to act as a selective adsorption agent and to its...

The substitution of complex hydrides and Ni- and noble metal-based catalysts in the synthesis of pharma and fragrance products is a relevant topic in the green chemistry scenario. Here, we report that non-toxic, non-noble metal-based Cu/SiO2 catalysts are effective and very selective in the hydrogenation of α,β-unsaturated ketones, esters and sulfo...

Hydrodeoxygenation of lignin is a fundamental step in biomass valorisation for the reduction of the oxygen content and the synthesis of a wide range of products. Vanillin is a lignin model compound containing an aldehydic group attached to an aromatic ring. Pd nanoparticles are particularly active in the hydrogenation of carbonyl groups and the sub...

The lack of supported versions of the tris[(1-benzyl-1H-1,2,3-triazol-4-yl)methyl]amine (TBTA) ligand, suitable for flow-chemistry applications at scale, prompted us to develop a new route for the immobilization of such tris-triazole chelating units on highly cross-linked polystyrene resins. With this aim, the preparation of the known TBTA-type mon...

The development of novel delivery systems capable of enhancing the antibody binding affinity and immunoactivity of short length saccharide antigens is at the forefront of modern medicine. In this regard, gold nanoparticles (AuNPs) raised great interest as promising nano-vaccine platform, as they do not interfere with the desired immune response and...

The selective oxidation of veratryl alcohol as lignin-derived compound was studied under mild conditions, using Au-Cu catalysts synthesized from pre-formed nanoparticles with different Au:Cu molar ratios. Bimetallic catalysts show higher activity compared to monometallic counterparts, highlighting a clear synergistic effect. By comparing the physic...

Palladium nanoparticles (Pd NPs) synthesized by the metal vapor synthesis technique were supported on poly(4-vinylpyridine) 2% cross-linked with divinylbenzene (Pd/PVPy). Transmission electron microscopy revealed the presence of small metal nanoparticles (dm = 2.9 nm) highly dispersed on the PVPy. The Pd/PVPy system showed high catalytic efficiency...

The effect of support, stabilizing agent, and Pd nanoparticles (NPs) size was studied for sodium muconate and t,t-muconic acid hydrogenation to bio-adipic acid. Three different activated carbons (AC) were used (Norit, KB, and G60) and carbon morphology did not affect the substrate conversion, but it greatly influenced the adipic acid yield. 1% Pd/K...

Asparenydiol, which is an important natural compound with potential pharmacological activities, was synthesized through two Sonogashira­ cross-coupling reactions catalyzed by supported Pd and Cu catalysts and by a Mitsunobu etherification. The optimization of the Sonogashira­ couplings allowed the use of catalysts supported on different matrices wi...

Palladium nanoparticles (NP) immobilized on metal scavengers (Smopex®-234, Smopex®-111, PVPy, 1% w/w) have been tested in the acyl Sonogashira reactions between terminal acetylenes and acid chlorides. Pd/PVPy resulted especially effective in the synthesis of alkynyl ketones with different stereoelectronic properties, even working with a very low am...

Au nanoparticles, generated by the metal vapor synthesis technique, were supported onto cerium oxycarbonate monohydrate (Ce2O(CO3)2·H2O) giving [email protected]2O(CO3)2·H2O. The obtained heterogeneous catalyst was used in the aerobic allyl alcohol oxidation reaction performed in toluene, showing a notably higher catalytic substrate conversion and...

The catalytic performance of a series of 1 wt % Pd/C catalysts prepared by the sol-immobilization method has been studied in the liquid-phase hydrogenation of furfural. The temperature range studied was 25–75 °C, keeping the H2 pressure constant at 5 bar. The effect of the catalyst preparation using different capping agents containing oxygen or nit...

H2 utilization as a green energy carrier involved a growing interest towards inorganic H2 permeable membranes, useful for its separation and purification. On this regard, Pd resulted to be the dominant membrane material due to its particular behavior to be fully H2 perm-selective with respect to all the other gases. In the last decade, composite Pd...

This Handbook is part of the EU CBRN CoE Project65 “Strengthening chemical and biological waste management in Central Asia countries for improved security and safety risk mitigation” – CABICHEM (http://www.cabichem.eu/index.php/en/) The book is implemented by the CNR - Institute of Chemical Sciences and Technologies (Milan, Italy) and Fondazione FO...

N-Doped TiO2 materials were used as support for the bimetallic gold-platinum nanoparticles catalysts. Via the sol immobilization technique, the metal particle dimension varied during the immobilization on the different supports. The prepared TiO2 samples were characterized by X-ray diffraction (XRD), N2 physisorption (BET) and X-ray photoelectron s...

The role of carbonaceous deposits (coke) formed in dehydrogenation catalysis has been extensively investigated over the last decades mainly with respect to the deactivation of metal-based and metal-free heterogeneous catalysts. Although much less emphasized, coke deposits grown on selected metal-oxides have also been described as active and selecti...

The addition of a specific amount of silica (10 wt.%) to zirconia was found to significantly influence the morphological and electronic properties of supported copper nanoparticles in a Cu/ZrO2-SiO2 catalyst. The so-developed catalyst was tested in the methanol steam reforming reaction and reached at 3500 h⁻¹ of space velocity a hydrogen productivi...

Anion exchange membrane fuel cells (AEMFCs) offer several important advantages with respect to proton exchange membrane fuel cells, including the possibility of avoiding the use of platinum catalysts to help overcome the high cost of fuel cell systems. Despite such potential benefits, the slow kinetics of the hydrogen oxidation reaction (HOR) in al...

DPU and SOL immobilisation have been used to prepare 1 %AuAg/TiO2 with internal ratio 1 : 1 and 4 : 1 which have been studied as fresh, calcined in air at 300 °C and reduced at 550 °C in H2. TEM‐EDS, XPS, UV‐Vis and CO‐DRIFT allowed to characterize the samples in terms of particle size, particle composition, exposure and oxidation state of metals....

sodium muconate and trans,trans‐muconic acid were heterogeneously hydrogenated to adipic acid, a strategic intermediate for the industry of polyamides and high performance polymers. Hydrogen pressure, metal to substrate ratio, substrate concentration and reaction temperature were varied to study the effect of these parameters on the reaction produc...

In this study, niobia-based materials have been used as supports for Pt nanoparticles and used in the hydrogenation of furfural. The incorporation of dopants (W6+ and Ti4+) in the Nb2O5 structure induced modifications in the surface acidity of the support; in particular, the addition of W6+ increased the amount of Lewis acid sites, while the additi...

The synthesis, characterization and catalytic performance of a conceptually simple, novel NbOx-SiO2 catalyst are here described. The niobium(V)-silica catalyst was prepared starting from cheap and viable reactants, by alkaline deposition of NH4Nb(C2O4)2·H2O in the presence of fructose as a stabilizer and subsequent calcination. The NbOx-SiO2 solid...

Beta zeolite has been functionalized with ca. 2 wt.% Fe to obtain catalysts for the NH3-SCO reaction. Iron deposition was performed on the zeolite surface by solvated metal atom dispersion (SMAD) and ionic-exchange (IE) procedures. ZSM-5 was selected as reference structure known to assure high dispersion of isolated centers when functionalized with...

Electrochemical CO2 reduction reaction (CO2RR), is a promising technology for combining carbon dioxide reutilization and renewable electricity storage. For economic feasibility, better catalysts are required to overcome current limitations such as high overpotentials, poor faradaic efficiencies, and low current densities. Here we investigate size a...

Pterostilbene, an important polyphenolic compound with interesting biological activities, has been efficiently synthesized through a Mizoroki-Heck reaction catalyzed by commercially available Pd catalysts immobilized onto heterogeneous supports. The synthesis has been transposed in a continuous flow reactor, following two different retrosynthetic a...

Palladium catalysts supported by a mesoporous form of sulfonated poly-divinylbenzene, Pd/µS-pDVB10 (1%, w/w) and Pd/µS-pDVB35 (3.6% w/w), were applied to the direct synthesis of hydrogen peroxide from dihydrogen and dioxygen. The reaction was carried for 4 h out in a semibatch reactor with continuous feed of the gas mixture (H2/O2 = 1/24, v/v; tota...

Hybrid Au-CuO NPs supported on carbon (Vulcan-XC72) with different Au/Cu molar ratios (i.e. 13/1, 4/1, 1/1 and 1/17) were synthesized by solvated metal atoms dispersion (SMAD) approach. (HR)-TEM, STEM-EELS maps and EXAFS meas-urements showed the presence of Au-CuO core-shell hetero-structure having narrow size distributions (mean diameter < 4.7 nm)...

Carbon nanofibers (CNFs) have been functionalized by introducing O, N, and P containing groups in order to investigate the effect of support functionalization in Ru catalysed hydroxymethyl furfural (HMF) and levulinic acid (LA) hydrogenation. In the case of HMF, despite the fact that no effect on selectivity was observed (all the catalysts produced...

Hydrogen reduction of an Ir(I) complex featured by a bulky N-heterocyclic carbene (NHC) ligand in dichloromethane gave small-sized (1.8 nm) Ir nanoparticles (NPs) decorated with NHC ligands (IrNHC). 1,4-Dioxane solutions of the latter particles were successfully applied to convert glycerol into lactic acid in the presence of NaOH (i.e. 1 mol equiva...

In the present study, the efficiency and selectivity and the role of surface groups of hydroxyapatite in the Cr(III) trapping, present in solution as single species or in co-presence of Ni(II) and Pb(II), have been investigated. Transmission electron microscopy (TEM) analysis and synchrotron radiation X-ray powder diffraction (XRPD) measurements pr...