Marcello Marelli

Italian National Research Council | CNR · SCITEC - Istituto di scienze e tecnologie chimiche “Giulio Natta”

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...

The substitution of fossil-based monomers in the thermosetting formulations is a fundamental issue to face the environmental concerns related to the use of traditional resins. In this paper, styrene-free thermosetting resins were prepared to start from vegetable oils with different compositions and unsaturation degrees, namely soybean, hempseed, an...

A simple organosilane-grafting protocol has been used for the preparation of a copper heterogeneous catalyst with tunable wettability properties. A series of Cu/SiO2 trietoxyoctylsilane-modified systems with gradually reduced alcoholphilicity has been used in the hydrogenation of the platform molecule γ-valerolactone into 1,4-pentandiol, a valuable...

A new process for the selective hydrogenation of γ-valerolactone (GVL) to 1,4-pentanediol (1,4-PDO), interesting biobased monomer, has been set up. It relies on the use of a non-noble, nontoxic metal such as Cu on a very simple oxide support, namely silica in a green solvent such as Cyclopentyl Methyl Ether (CPME). The role of the solvent was not o...

Biochar nanoparticles (BC NPs), produced by low temperature pyrolysis (350 °C) of mi-croalgae (Nannochloropsis sp.) and nutshells, are proposed as low-cost and sustainable co-catalysts to promote the photocatalytic activity of TiO2 nanotube (NT) arrays towards the degradation of methylene blue (MB) used as an organic pollutant model molecule. BC NP...

Gelatin is a costless polypeptide material of natural origin, able to form hydrogels that are potentially useful in biomaterial scaffold design for drug delivery, cell cultures, and tissue engineering. However, gelatin hydrogels are unstable at physiological conditions, losing their features only after a few minutes at 37 °C. Accordingly, treatment...

In this paper we introduce the use of molecular metal clusters as precursors for the in-situ formation of nanoparticles with high activity and surprising stability as electrocatalysts in energy conversion....

A laser ablation–inductively coupled plasma–mass spectrometry (LA–ICP–MS) based method is proposed for the quantitative determination of the spatial distribution of metal nanoparticles (NPs) supported on planar substrates. The surface is sampled using tailored ablation patterns and the data are used to define three-dimensional functions describing...

The chemoselective conversion of a specific functional group in a multifunctional substrate is of great importance in the chemical industry to obtain cost efficient, sustainable and waste free processes. This work focuses on the chemoselective amination of halogenated aromatic aldehydes with dimethyl amine towards halogenated aromatic amines, a raw...

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...

The development of a prototype apparatus to perform patterned Chemical Vapour Deposition (CVD) on planar substrates is presented. The system consists of a fixed head which produces and drives a tiny spot of vapors of a suitable organometallic precursor over the substrate, which is mounted on a heatable and movable stage. WO3 deposition from W(CO)6...

Passive air samplers (PASs) have been used for mapping gaseous mercury concentration in extensive areas. In this work, an easy-to-use and -prepare gold nanoparticle (NP)-based PAS has been investigated. The PAS is constituted of a microfibrous quartz disk filter impregnated of gold NP photo-growth on TiO2 NPs (Au@TiO2) and used as gaseous mercury a...

Hematite (α-Fe2O3) is an Earth-abundant indirect n-type semiconductor displaying a band gap of about 2.2 eV, useful for collecting a large fraction of visible photons, with frontier energy levels suitably aligned for carrying out the photoelectrochemical water oxidation reaction under basic conditions. The modification of hematite mesoporous thin f...

Anisotropic gold nanoparticles (AuNPs), with their unique physical and optical properties, are emerging as smart and key nanomaterials, and are being exploited in many crucial fields. To further improve their range of action, anisotropic AuNPs have been coupled with semiconductors, mainly TiO2 (titania), receiving great interest as powerful platfor...

Hematite (α-Fe2O3) is a promising and earth-abundant material for solar fuel production and Si doping has been employed as a general strategy to improve its performance. However, an atomistic description that reconciles the modifications that Si doping induces on the morphology, crystalline lattice, electronic and magnetic properties of α-Fe2O3 has...

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...

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...

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 activity of two Cu/SiO2 catalysts prepared by the chemisorption hydrolysis technique has been tested in the hydrogenation reaction of 3-methyl-cyclohexanone. Both catalysts were found to be very active at 60 °C and 1 atm of H2. Characterization of the materials by FT-IR of adsorbed CO and TEM put in light the presence of well formed Cu cristall...

Understanding the interplay between the structural, chemical and physical properties of nanomaterials is crucial for designing new devices with enhanced performance. In this regards, doping of metal oxides is a general strategy to tune size, morphology, charge, lattice, orbital and spin degrees of freedoms and has been shown to affect nanomaterials...

Gelatin is a biopolymer with interesting properties that can be useful for biomaterial design for different applications such as drug delivery systems, or 3D scaffolds for tissue engineering. However, gelatin suffers from poor mechanical stability at physiological temperature, hence methods for improving its properties are highly desirable. In the...

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)...

Passive sampling systems (PASs) are a low cost strategy to quantify Hg levels in air over both different environmental locations and time periods of few hours to weeks/months. For this reason, novel nanostructured materials have been designed and developed. They consist of an adsorbent layer made of titania nanoparticles (TiO2NPs, ≤25 nm diameter)...

Hematite-based photoanodes were used for the photoelectrocatalysed batch oxidation of As(III) in water at pH 7 and 10. Tests were carried out at different As(III) initial concentrations, ranging from 150 μg/L to 30 mg/L. With no pre-treatments, an initial inactive period of 40–50 min was always observed at the beginning of every test. This initial...

Hematite (α-Fe2O3) is one of the most promising photoanode materials for photoelectrochemical (PEC) water splitting although great challenges hinder high performance. Silicon-doped α-Fe2O3 shows improved PEC activity but the relationship among dopant content and enhanced conductivity, structure, and particle morphology is only poorly understood. He...

The present study reports on a simple preparation strategy of a hybrid catalyst, TiO2/HKUST-1, containing TiO2 anatase nanoparticles (NPs) with tailored morphology and photocatalytic activity coupled with a porous metal-organic framework (MOF), namely HKUST-1, as an advanced material for the CO2 photocatalytic reduction. In detail, TiO2/HKUST-1 cat...

The synthesis of N-heterocyclic carbene (NHC)-stabilized palladium nanoparticles (PdNPs) by an entirely new strategy comprising the NHC functionalization of ligand-free PdNPs obtained by metal vapor synthesis is described. Detailed characterization confirms the formation of very small monodisperse PdNPs (2.3 nm) and the presence of the NHC ligand o...

Herein, we report a one-pot wet chemical method adopted to synthesize ad hoc MnO2 nanoparticles. By varying both the manganese salt precursors (e.g. sulphate or chloride) and the oxidizing agents (e.g. ammonium persulphate, potassium permanganate or potassium bromate), we succeeded in tailoring MnO2 structural, morphological and surface features. H...

Here we report the synthesis of a core - CuI/shell - CuO nanostructure that depending on the applied potential works as photocathode or photoanode in neutral pH upon visible light irradiation. Under cathodic polarization, this material generates a stable cathodic photocurrent but functions as photoanode when anodic polarization is applied. In this...

Cobalt oxide fibres are synthesised via electro-spinning followed by calcination in air at 600 °C. Texture, morphology and surface composition of the fibres, as well as phase of the oxide formed are investigated by means of a combination of characterisation techniques. The electrochemical performance of the electro-spun Co3O4 fibres as anode materi...

In biomedical applications of nanoparticles (NP), the proper choice of surface chemistry is a crucial aspect in their design. The nature of the coating can heavily impact on the interaction of NPs with biomolecules, affect the state of aggregation, and ultimately determine their biological fate. As such, protein corona formation, and the aggregatio...

The development of fuel cells is hampered by high costs, a large part of which is due to platinum (Pt) electrocatalysts. Complete removal of Pt is a difficult if not impossible task for proton exchange membrane fuel cells (PEM-FCs). The anion exchange membrane fuel cell (AEM-FC) has been often proposed as a solution as non-Pt metals may be employed...

In article number 1601031, Alberto Naldoni, Vladimir M. Shalaev, and co-workers present plasmonic titanium nitride (TiN) nanoparticles on top of TiO2 nanowires, which strongly improve the activity toward photoelectrochemical water splitting. Plasmonic TiN provides efficient generation of hot electrons due to a broadband absorption and improved elec...

Pure and titanium- or silicon-doped iron oxide fibres are synthesised by electro-spinning over conductive fluorine doped tin oxide (FTO)/glass substrates, and the effect of the type of dopant on the morphology of the fibres and the crystalline phase of the oxide is investigated by means of several complementary characterisation techniques. Results...

The photodegradation of the highly toxic o-toluidine pollutant was deeply investigated both under UV and solar irradiations by using three different semiconductors: pure ZnO, Bi-impregnated ZnO, and Bi2O3 nanopowders (synthesized by precipitating method). All the samples were deeply characterized on structural, morphological, surface, and optical p...

Exhaustive hydrolysis of a mixture of [La4(CO3)(O2CNBu2)10] and [Cu(O2CNBu2)(py∗)2] (py∗ = 4-dimethylamino pyridine) in molar ratio 1/2 corresponding to a La/Cu molar ratio 2/1 was carried out in toluene at room temperature. The carbamato derivatives of lanthanum and copper can be easily prepared by extraction of the metal ions from aqueous solutio...

One of the biggest obstacles to the diffusion of fuel cells is their cost, in large part due to platinum catalysts. Here, a platinum-free fuel cell was studied that employs a mixed carbon-CeO2 supported palladium anode catalyst and produces peak power densities of more than 500 mW cm-2.

The use of hot electrons generated from the decay of surface plasmons is a novel concept that promises to increase the conversion yield in solar energy technologies. Titanium nitride (TiN) is an emerging plasmonic material that offers compatibility with complementary metal-oxide-semiconductor (CMOS) technology, corrosion resistance, as well as mech...

The chronic toxicity of ZnSO4 and ZnO nanoparticles has been studied in Daphnia magna also considering the life cycle parameters beyond the standard 21-day exposure time. Specimens have been individually followed until the natural end of their life, and some of them sampled for microscopic analyses at 48 h, 9 and 21 days. Despite the low level of e...

We report an interesting new class of bifunctional electrocatalysts, Pd/C-CeO2 , with excellent activity and stability for the hydrogen oxidation reaction (HOR) under alkaline conditions. The unique structure of palladium deposited onto a mixed support of Vulcan XC-72 carbon and CeO2 consists of Pd metal preferable deposited on the ceria regions of...

Photocatalytic reactions could enhance the share of chemicals produced through renewable sources. The efficiency of photocatalysts drastically depends on light absorption, on surface energy of the crystals, and on the properties of nano-building blocks assembled in devices. Here, we show that photoelectrochemical water oxidation on brookite TiO2 na...

A new protocol to synthesize size-controlled Au nanoparticles (NPs) loaded onto vertically aligned anatase TiO2 nanotubes arrays (TNTAs) prepared by electrochemical anodization is reported. Ligand-free Au NPs (< 10 nm) were deposited onto anatase TNTAs supports, finely tuning the Au loading by controlling the immersion time of the support into meta...

Nanostructured MnO2 has unique electrocatalytic properties towards the Oxygen Reduction Reaction (ORR, the main cathodic reaction in metal-air devices), representing an excellent alternative to the expensive platinum. Herein, we report the hydrothermal synthesis of bare and 5% Ti-doped α-MnO2 nanoparticles using two different oxidizing agents, name...

The use of hot electrons generated from the decay of surface plasmons is a new paradigm to increase the conversion yield in solar energy technologies. Titanium nitride (TiN) is an emerging plasmonic ceramic that offers compatibility with CMOS technology, corrosion resistance, as well as mechanical strength and durability thus outperforming noble me...

: Doping hematite with different elements is a common strategy to improve the electrocatalytic activity towards the water oxidation reaction, although the exact effect of these external agents is not yet clearly understood. Using a feasible electrophoretic procedure, we prepared modified hematite films by introducing in the deposition solution Ti(I...

The role of soluble zinc has been determined in Daphnia magna by a morphological approach, integrating a previous paper in which the ultrastructural damages to gut epithelial cells have been studied after ZnO nanoparticles exposure. In the present paper, the toxicity and morphological effects of soluble zinc from ZnSO4 have been determined in a 48-...

Hetero-nanoparticles represent an important family of composite nanomaterials that, in the last years, is attracting ever growing interest. Here, we report a new strategy for the synthesis of water dispersible cobalt ferrite nanoparticles (CoxFe3-xO4 NPs) decorated with ultrasmall (2-3 nm) gold nanoparticles (Au NPs). The synthetic procedure is bas...

Photoanodes for solar water splitting require the use of a large applied potential to sustain high photocurrent. This has been conventionally addressed by depositing electrocatalysts on semiconductors to boost the kinetics of water oxidation. Herein, it is shown that the advancement in onset potential (VON) of hematite (α-Fe2O3) is not regulated by...

Ultrafine Pd nanoparticles (dm = 2.3 nm), obtained by metal vapor synthesis technique, were immobilized into a poly(4-vinylpyridine)-based porous monolith by means of a new synthetic approach. The synthesis involves stabilization of Pd nanoparticles with 4-vinylpyridine ligand and their subsequent immobilization into the monolith by radical co-poly...

One of the biggest obstacles to the dissemination of fuel cells is their cost, a large part of which is due to platinum (Pt) electrocatalysts. Complete removal of Pt is a difficult if not impossible task for proton exchange membrane fuel cells (PEM-FCs). The anion exchange membrane fuel cell (AEM-FC) has long been proposed as a solution as non-Pt m...

Nanostructured titanium oxide difluoride embedded in a matrix of amorphous carbon was synthesized by pyrolysis of d-fructose in the presence of titanium tetrafluoride (optimal Ti/fructose molar ratio = 5.5), both in the solid state at ca. 150 °C and in suspension of 1,2-dichloroethane at reflux temperature. The resulting solid materials were charac...

Here, we report new gas diffusion electrodes (GDEs) prepared by mixing two different pore size carbonaceous matrices and pure and silver-doped manganese dioxide nanopowders, used as electrode supports and electrocatalytic materials, respectively. MnO2 nanoparticles are finely characterized in terms of structural (X-ray powder diffraction (XRPD), en...

Self-standing and flexible paper-like electrodes consisting of nano-sized Co3O4 nanoparticles encapsulated in nitrogen-doped graphite-like carbon fibers are synthesized by electrospinning followed by thermal treatment. Several studies have recently reported that encapsulating nano-sized metal oxides that display conversion reaction, such as mangane...

One of the biggest obstacles to the dissemination of fuel cells is their cost, alarge part of which is due to platinum (Pt) electrocatalysts.Complete removal of Pt is adifficult if not impossible task for proton exchange membrane fuel cells (PEM-FCs). The anion exchange membrane fuel cell (AEM-FC) has long been proposed as asolution as non-Pt metal...

Aiming at understanding how plasmonic reactions depend on important parameters such as metal loading and strong metal–support interaction (SMSI), we report the plasmonic photodegradation of formic acid (FA) under green LED irradiation employing three TiO2 supports (stoichiometric TiO2, N-doped TiO2, black TiO2) modified with Au nanoparticles (NPs)...

The development of a scanning reactor for planar catalysts (SCR-PC) is here presented. With respect to other existing models, this reactor is able to scan catalysts even with low turnover frequencies, with a minimum sensed circular area of about 6 mm diameter. The downstream gas analysis is performed with a quaprupole mass spectrometer. The apparat...

Au- and iron-based magnetic nanoparticles (NPs) are promising NPs for biomedical applications due to their unique properties. The combination of a gold coating over a magnetic core puts together the benefits from adding the magnetic properties to the robust chemistry provided by the thiol functionalization of gold. Here, the use of Au-coated magnet...

The study of the semiconductor/electrocatalyst interface in electrodes for photoelectrochemical water splitting is of paramount importance to obtain enhanced solar-to-fuel efficiency. Here, we take into consideration the multiple effects that a thin layer of photodeposited amorphous Ni-oxyhydroxide (NiOOH) induces on hematite (α-Fe2O3) photoanodes....

The direct in-situ stabilization of an anatase-based nanocrystalline photocatalyst (Degussa P25) was obtained by sintering the catalyst powder in presence of Zr4+ organic salts. This approach allows the doping of an already-formed nanocrystalline photocatalyst instead of introducing the dopant in the crystal lattice during the catalyst synthesis. T...

Mitochondria, as recently suggested, might be involved in iron sensing and signalling pathways in plant cells. For a better understanding of the role of these organelles in mediating the Fe deficiency responses in plant cells, it is crucial to provide a full overview of their modifications occurring under Fe-limited conditions. The aim of this work...

Exploiting plasmonic Au nanoparticles to sensitize TiO2 to visible light is a widely employed route to produce efficient photocatalysts. However, a description of the atomic and electronic structure of the semiconductor sites in which charges are injected is still not available. Such a description is of great importance in understanding the underly...

Cathodoluminescence spectroscopy is profitably exploited to study energy transfer mechanisms in Au and Pt/black TiO2 heterostructures. While Pt nanoparticles absorb light in the UV region, Au nanoparticles absorb light by surface plasmon resonance and interband transitions, both of them occurring in the visible region. The intra-bandgap states (oxy...