Papers by Giuliano Giambastiani
Chimia, Sep 27, 2017
The last few years have witnessed aw onderful technological renaissance that boosted the developm... more The last few years have witnessed aw onderful technological renaissance that boosted the development of carbon-based nanomaterials (CNMs) doped with light heteroelements and featuring hierarchical porous architectures as valuable metal-free catalysts for an umber of key industrial transformations. To date, several approaches to their synthesis have been developed, although many of them lack any real control of the final doping and composition. In contrast, chemical functionalization offers au nique and powerful tool to tailor CNMs' chemical and electronic surface properties as af unction of their downstream application in catalysis. Different catalytic processes (hydrolysis/esterification/transesterification reactions, C-C bond forming reactions, CO 2 derivatization into products of added value and electrochemical oxygen reduction reactions (ORR)) can be conveniently promoted by these materials. In addition, selected examples from this series offer av aluable platform for the in-depth comprehension of the underlying reaction mechanisms. This perspective article offers an overview on the main examples of ad hoc chemically decorated CNMs successfully exploited as metal-free catalysts, highlighting at the same time the importance of the surface chemistry control for the design of more active, metal-free and single-phase heterogeneous catalysts.
Carbon, Nov 1, 2016
The spatial confinement of water in graphene-oxide membranes has been studied at room temperature... more The spatial confinement of water in graphene-oxide membranes has been studied at room temperature using deep inelastic neutron scattering. This technique enabled the non-invasive measurement of water levels in hydrated and dried specimens, as well as of proton mean kinetic energies. For the first time, the latter observables are provided for the special case of graphene-oxide membranes. Absolute values of the mean kinetic energy provide direct insight into the local chemical environment of the proton under spatial confinement. In conjunction with parallel X-ray diffraction, atomic force microscopy, and thermal-gravimetric analysis measurements, our experimental results show that the characteristic, quasi-twodimensional confinement of water between graphene-oxide sheets results in a binding environment remarkably similar to that in the bulk. We surmise that this behaviour arises from a small fraction of hydroxyl groups relative to water molecules in graphene-oxide membranes, as well as the predominance of non-specific and weak interactions between water and the underlying nanostructured substrate.
ChemSusChem
Ni-based catalysts prepared through impregnation of depleted uranium oxides (DU) have successfull... more Ni-based catalysts prepared through impregnation of depleted uranium oxides (DU) have successfully been employed as highly efficient, selective, and durable systems for CO 2 hydrogenation to substituted natural gas (SNG; CH 4 ) under an autothermal regime. The thermo-physical properties of DU and the unique electronic structure of f-block metal-oxides combined with a nickel active phase, generated an ideal catalytic assembly for turning waste energy back into useful energy for catalysis. In particular, Ni/UO x stood out for the capacity of DU matrix to control the extra heat (hot-spots) generated at its surface by the highly exothermic methanation process. At odds with the benchmark Ni/γ-Al 2 O 3 catalyst, the double action played by DU as a "thermal mass" and "dopant" for the nickel active phase unveiled the unique performance of Ni/UO x composites as CO 2 methanation catalysts. The ability of the weakly radioactive ceramic (UO x ) to harvest waste heat for more useful purposes was demonstrated in practice within a rare example of a highly effective and long-term methanation operated under autothermal regime (i. e., without any external heating source). This finding is an unprecedented example that allows a real stepforward in the intensification of "low-temperature" methanation with an effective reduction of energy wastes. At the same time, the proposed catalytic technology can be regarded as an original approach to recycle and bring to a second life a lesssevere nuclear by-product (DU), providing a valuable alternative to its more costly long-term storage or controlled disposal.
Journal of Physics: Conference Series, 2017
Acta Crystallographica Section A Foundations and Advances, 2019
In the past century, the global temperature rose by 0.7 K. CO2 concentration in the atmosphere, c... more In the past century, the global temperature rose by 0.7 K. CO2 concentration in the atmosphere, contributing by more than 60% to global warming, overcame 410 ppm in 2019. MOFs are a potential alternative to all-inorganic materials in applications requiring gas adsorption. Their performances can be optimized using one properly functionalized ligand or a mixture therefrom. The four mixed-ligand MOFs Zn-H/NO2, Zn-H/NH2, Zn-NO2/NH2 and Zn-H/NO2/NH2, synthesized employing 4,4'bipyrazole, 3-nitro-4,4'-bipyrazole and 3-amino-4,4'-bipyrazole, were characterized in the solid state. Their crystal structures were assessed by PXRD, they are isoreticular to the end-members Zn-H [1], Zn-NO2 [2] and Zn-NH2 [3], showing a 3-D open frameworks with 1-D square/rhombic channels. The ligand stoichiometric ratio was determined independently, with an excellent agreement, by 13C CPMAS solid-state NMR and PXRD. DSC and PXRD, upon application of the Vegard law, confirmed the formation of solid solutions. The four MOFs are thermally stable (Tdec = 708-726 K) and, as proved by variable-temperature PXRD, show permanent porosity. N2 adsorption at 77 K revealed BET surface areas in the range 400-600 m2/g. CO2 adsorption capacity, isosteric heat of adsorption (Qst) and CO2/N2 selectivity (at 1 bar and 298 K), were compared with those of their end-members. The amino-decorated compounds show higher Qst values and better selectivity vs. the nitro-tagged analogues; moreover, tag "dilution" is beneficial compared to the end-members.
Materials Today Energy, 2018
This work describes a straightforward approach to the production of highly-performing and costeff... more This work describes a straightforward approach to the production of highly-performing and costeffective C-based materials for energy storage application while proposing an original and effective method to the control of the final material morphology. Indeed, robust few-layer graphene-like and highly open-cell structures have been prepared by a modified chemical activation procedure starting from costless sugar/salt mixtures. The as-prepared C-samples ensure high ion-accessible surface area and low ion transport resistance, two key features for the fabrication of effective electrochemical double layer supercapacitors. A selected sample from this series exhibits high specific capacitance (C g ) (312 and 234 F g À1 at 0.5 and 50 A g À1 , respectively, in 0.5 M H 2 SO 4 ), particularly at high current density values, along with excellent cycling stability and C g retention for increasing chargeedischarge rates.
Journal of Materials Chemistry B, 2016
An efficient drug delivery system through a straightforward approach to multi-walled carbon nanot... more An efficient drug delivery system through a straightforward approach to multi-walled carbon nanotube decoration.
ChemPlusChem, 2015
The main feature of the fruitful collaboration between the four research centers involved in this... more The main feature of the fruitful collaboration between the four research centers involved in this study is the aim at addressing specific goals while being driven by curiosity.M ost importantly,t he complementary expertise of the groups involved (chemists and physicists experienced in organic and organometallic synthesis, material science, catalysis, and spectroscopy) is of fundamental importance to meet the specific needs of highly interdisciplinary subjects like those related to the surface engineering of CNTs. The collaboration activity led by the ICCOM team stems from joint research interests supported by common project grants (European and National) including all four research institutes, in the field of nanomaterials technology with applications spanning from sustainable catalytic processes (FreeCats FP7 NMP project) to life science (Nanomax Encoder &F irb Te ranostica).
Journal of Materials Chemistry, 2010
Figure S1: Microwave heating ramp showing the applied power and the instant temperature used duri... more Figure S1: Microwave heating ramp showing the applied power and the instant temperature used during the GOT4 synthesis. Red curve: temperature (°C), blue curve: pressure (bar), black curve: energy (kW).
Inorganic Chemistry, 2012
Dalton Transactions, 2011
C(25) 5754(1) -4450(1) -2319(2) 22(1) C(26) 6280(1) -4887(2) -2021(1) 22(1) C(27) 6655(1) -4917(2... more C(25) 5754(1) -4450(1) -2319(2) 22(1) C(26) 6280(1) -4887(2) -2021(1) 22(1) C(27) 6655(1) -4917(2) -2738(1) 21(1) C(28) 7213(1) -5340(2) -2853(2) 29(1) C(29) 7447(1) -5356(2) -3649(2) 35(1) C(30) 7137(1) -4930(2) -4374(2) 31(1) C(31) 6598(1) -4495(2) -4288(1) 26(1) C(32) 7185(1) -530(2) -1640(1) 24(1)
New Functionalized Vinyl Monomers by Ethylene‐(Functionalized)‐Norbornene Hetero‐Trimerization Catalyzed by Cobalt(II)‐(Imino)pyridine Complexes
Advanced Synthesis & Catalysis, 2008
On activation by MAO the (imino)pyridine cobalt(II) complex CoCl2N2 catalyzes the enchainment of ... more On activation by MAO the (imino)pyridine cobalt(II) complex CoCl2N2 catalyzes the enchainment of one norbornene (NB) molecule with two ethylene molecules to give exo‐2,exo‐3‐ethylvinylnorbornane with high activity and complete diastereoselectivity. Turnover frequencies [TOF, mol NB (mol Co×h)−1] as high as 270,000 have been obtained. The 2E‐1NB hetero‐trimerization reaction has been also accomplished with NBs bearing polar substituents such as norbornenemethanol and norbornenecarboxylic acid provided that the substrate is protected with triisobutylaluminum and the less sterically demanding complex CoCl2N2 is used as catalyst precursor. A mechanism for the hetero‐trimerization reactions is proposed on the basis of experimental evidence.
Solvent-assisted ligand incorporation (SALI) of the ditopic linker 5-carboxy-3-(4-carboxybenzyl)t... more Solvent-assisted ligand incorporation (SALI) of the ditopic linker 5-carboxy-3-(4-carboxybenzyl)thiazolium bromide [(H 2 PhTz)Br] into the zirconium metal-organic framework NU-1000 [Zr 6 O 4 (OH) 8 (H 2 O) 4 (TBAPy) 2 , where NU = Northwestern University and H 4 TBAPy = 1,3,6,8-tetrakis(p-benzoic-acid)pyrene], led to the SALIed NU-1000-PhTz material of minimal formula [Zr 6 O 4 (OH) 6 (H 2 O) 2 (TBAPy) 2 (PhTz)]Br. NU-1000-PhTz has been thoroughly characterized in the solid state. As confirmed by powder X-ray diffraction, this material keeps the same three-dimensional architecture of NU-1000 and the dicarboxylic extra linker bridges adjacent [Zr 6 ] nodes ca. 8 Å far apart along the crystallographic c-axis. The functionalized MOF has a BET specific surface area of 1560 m 2 /g, and it is featured by a slightly higher thermal stability than its parent material (T dec = 820 vs. 800 K, respectively). NU-1000-PhTz has been exploited for the capture and separation of two pollutant gases: carbon dioxide (CO 2 ) and nitrous oxide (N 2 O). The high thermodynamic affinity for both gases [isosteric heat of adsorption (Q st ) = 25 and 27 kJ mol -1 for CO 2 and N 2 O, respectively] reasonably stems from the strong interactions between these (polar) "stick-like" molecules and the ionic framework. Intriguingly, NU-1000-PhTz shows an unprecedented temperature-dependent adsorption capacity, loading more N 2 O in the 298 K ≤ T ≤ 313 K range but more CO 2 at temperatures falling out of this range. Grand canonical Monte Carlo simulations of the adsorption isotherms confirmed that the preferential adsorption sites of both gases are the triangular channels (micropores) in close proximity to the polar pillar. While CO 2 interacts with the thiazolium ring in an "end-on" fashion through its O atoms, N 2 O adopts a "side-on" configuration through its three atoms simultaneously. These findings open new horizons in the discovery of functional materials that may discriminate between polluting gases through selective adsorption at different temperatures.
ACS Applied Materials & Interfaces
The novel Zr IV-based PerFluorinated Metal-Organic Framework (PF-MOF) [Zr6O4(OH)4(TFS)6] (ZrTFS) ... more The novel Zr IV-based PerFluorinated Metal-Organic Framework (PF-MOF) [Zr6O4(OH)4(TFS)6] (ZrTFS) was prepared under solvent-free conditions using the commercially available tetrafluorosuccinic acid (H2TFS) as bridging ditopic linker. Since H2TFS can be seen as the fully aliphatic and perfluorinated C4 analogue of fumaric acid, ZrTFS was found to be isoreticular to zirconium fumarate (MOF-801). The structure of ZrTFS was solved and refined from X-ray Powder Diffraction data. Despite this analogy, the gas adsorption capacity of ZrTFS is much lower than that of MOF-801; in the former, the presence of bulky fluorine atoms causes a considerable windows size reduction. In order to have PF-MOFs with more accessible porosity, Post-Synthetic Exchange (PSE) reactions on (defective) MOF-801 suspended in H2TFS aqueous solutions were carried out. Despite the different H2TFS concentrations used in the PSE process, the exchanges yielded two mixed-linker materials of similar minimal formulae [Zr6O4(μ3-OH)4(μ1-OH)2.08(H2O)2.08(FUM)4.04(HTFS)1.84] (PF-MOF1) and [Zr6O4(μ3-OH)4(μ1-OH)1.83(H2O)1.83(FUM)4.04(HTFS)2.09] (PF-MOF2) (FUM 2-= fumarate), where the perfluorinated linker was found to fully replace the capping acetate in the defective sites of pristine MOF-801. CO2 and N2 adsorption isotherms collected on all samples reveal that both CO2 thermodynamic affinity (isosteric heat of adsorption at zero coverage, Qst) and CO2/N2 adsorption selectivity increase with the amount of incorporated TFS 2-, reaching the maximum values of 30 kJ mol-1 and 41 (IAST), respectively, in PF-MOF2. This confirms the beneficial effect coming from the introduction of fluorinated linkers in MOFs on their CO2 adsorption ability. Finally, solid-state density functional theory calculations were carried out to cast light on the structural features and on the thermodynamics of CO2 adsorption in MOF-801 and ZrTFS. Due to the difficulties in modelling a defective MOF, an intermediate structure containing both
Journal of Materials Chemistry C, 2020
The benzothiazolium-decorated NU-1000-BzTz MOF is a versatile material for carbon dioxide storage... more The benzothiazolium-decorated NU-1000-BzTz MOF is a versatile material for carbon dioxide storage and cyanide luminescence sensing in aqueous solutions.
Dalton Transactions, 2019
Highly versatile and robust organolanthanides as catalysts or catalyst precursors for a variety o... more Highly versatile and robust organolanthanides as catalysts or catalyst precursors for a variety of challenging transformations.
Sustainable Energy & Fuels, 2019
The pyrazole-based RuII unsymmetrical pincer hydride (tBuPNN*)RuH(CO) has been exploited as ammon... more The pyrazole-based RuII unsymmetrical pincer hydride (tBuPNN*)RuH(CO) has been exploited as ammonia borane and hydrazine bis(borane) dehydrogenation catalyst in THF solution at ambient temperature.
Journal of Materials Chemistry B, 2018
Phospholipids modified graphene oxide (GO–PL) shows enhanced compatibility with primary rat corti... more Phospholipids modified graphene oxide (GO–PL) shows enhanced compatibility with primary rat cortical astrocytes with respect to standard adhesion agents and non-functionalized GO.
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Papers by Giuliano Giambastiani