Retrofit of an Existing School in Italy with High Energy Standards

Abstract The Tito Maccio Plauto school was built in Cesena during late sixties and, conformingly to the period construction technologies and standards, is characterized by poor energy performances. The retrofit of the school is implemented in the framework of the School of the Future Project, funded by 7th Framework Programme. The objective is demonstrating the technical economical feasibility of deep energy renovation for public buildings, bound to last several decades after, avoiding the land use for new construction and improving the energy performances of the existing building stock. The actual consumptions for the different energy services were monitored and the occupancy profile of the school zones was analyzed. Starting from the preliminary monitoring it was possible to design the most suitable energy to achieve the initial targets: reduction of factor 4 of space heating energy uses, reduction of factor 3 of the overall energy uses. The measures involved: external insulation of facades and roof, partial insulation of the ground floor, replacement of windows with external moveable shading devices, complete renovation of the heating system, design and installation of a remote energy management system for the municipality schools, installation of a PV plant on the roof, mechanical ventilation system for classrooms. The last measure was implemented to fulfill the improvement of the indoor environment quality, another crucial issues the EU Project had to couple with. Detailed analyses, carried out with dynamic and national reference calculation tools, demonstrated the efficacy of the implemented measures, since all the relevant target were reached, as will be monitored during the monitoring phase of the project

In operando XAS investigation of reduction and oxidation processes in cobalt and iron mixed spinels during the chemical loop reforming of ethanol

FeCo2O4 and CoFe2O4 nanoparticles have been studied as oxygen carriers for the Chemical Loop Reforming (CLR) of ethanol. By using in operando X-ray absorption spectroscopy we have followed in real time the chemical and structural changes that take place on the materials as a function of temperature and reactive atmosphere (i.e. ethanol/water streams). During the first step of CLR for both oxides the most active chemical species are the cations in the tetrahedral sites, irrespective of their chemical nature. Quite rapidly the spinel structure is transformed into a mix of wustite-type oxide and metal alloys, but the formation of a metal phase is easier in the case of cobalt, while iron shows a marked preference to form wustite type oxide. Despite the good reducibility of FeCo2O4 imparted by the high amount of cobalt, its performance in the production of hydrogen is quite poor due to an inefficient oxidation by water steam, which is able to oxidize only the outer shell of the nanoparticles. In contrast, CoFe2O4 due to the residual presence of a reducible wustite phase shows a higher hydrogen yield. Moreover, by combining the structural information provided by X-ray absorption spectroscopy with the analysis of the byproducts of ethanol decomposition we could infer that FeCo2O4 is more selective than CoFe2O4 for the selective dehydrogenation of ethanol to acetaldehyde because of the higher amount of Fe(III) ions in tetrahedral sites

Nitrogen- and Fluorine-Doped Carbon Nanohorns as Efficient Metal-Free Oxygen Reduction Catalyst: Role of the Nitrogen Groups

The search of active, stable and low costs catalysts for the oxygen reduction reaction (ORR) is crucial for the extensive use of fuel cells and metal–air batteries. The development of metal-free catalysts, instead of platinum-based materials, can dramatically reduce the cost and increase the efficiency of these devices. In this work, carbon nanohorns (CNHs) have been covalently functionalized with N-containing heterocycles by the Tour reaction protocol and tested as metal-free ORR catalysts. The insertion of N-functionalities favored the complete reduction of oxygen to hydroxyl ions, while their absence favored the production of hydrogen peroxide. With the aim of determining the N-species responsible for the ORR activity of CNHs, photoemission and electrochemical measurements were combined. Results suggest that protonated N is the main species involved in the ORR process, facilitating the adsorption of oxygen, with their consequent reduction to neutral hydrogenated N species

Ag-Vanadates/GO Nanocomposites by Aerosol-Assisted Spray Pyrolysis: Preparation and Structural and Electrochemical Characterization of a Versatile Material

In this article, we describe the deposition by aerosol-assisted spray pyrolysis of different types of silver vanadate nanocomposites with and without graphene oxide (GO) on different substrates (carbon paper (CP) and fluorine-doped tin oxide (FTO)). When deposited on CP, different amounts of GO were added to the Ag and V precursor solution to study the effect of GO on the physicochemical properties of the resulting Ag-vanadate. It is shown that the addition of GO leads mainly to the formation of nanoparticles of the Ag2V4O11 phase, whereas Ag2V4O11 and Ag3VO4 are obtained without the addition of GO. The morphology and chemical properties of the composites were determined by scanning and transmission electron microscopies, X-ray diffraction, X-ray photoemission spectroscopy, and UV\u2013visible and Raman spectroscopies. In addition, the photoelectrochemical (PEC) properties of such composites were studied by CV, linear sweep voltammetry, and electrochemical impedance spectroscopy. The ideal AgxVOy and GO ratio was optimized for obtaining higher photocurrent values and a good stability. The results showed that the presence of GO improves the electrical conductivity of the catalyst layer as well as the electron injection from the oxide to the electrode surface. The deposition of pure Ag2V4O11 on FTO does not lead to samples with stable PEC performances. Samples grown on CP supports showed an efficient electrochemical detection of small amounts of ethylenediamine in water solution

Postsynthetic Metalated MOFs as Atomically Dispersed Catalysts for Hydroformylation Reactions

A manganese-based metal-organic framework with dipyrazole ligands has been metalated with atomically dispersed Rh and Co species and used as a catalyst for the hydroformylation of styrene. The Rh-based materials exhibited excellent conversion at 80 °C with complete chemoselectivity, high selectivity for the branched aldehyde, high recyclability, and negligible metal leaching

Indium selenide: An insight into electronic band structure and surface excitations

We have investigated the electronic response of single crystals of indium selenide by means of angle-resolved photoemission spectroscopy, electron energy loss spectroscopy and density functional theory. The loss spectrum of indium selenide shows the direct free exciton at similar to 1.3 eV and several other peaks, which do not exhibit dispersion with the momentum. The joint analysis of the experimental band structure and the density of states indicates that spectral features in the loss function are strictly related to single-particle transitions. These excitations cannot be considered as fully coherent plasmons and they are damped even in the optical limit, i.e. for small momenta. The comparison of the calculated symmetry-projected density of states with electron energy loss spectra enables the assignment of the spectral features to transitions between specific electronic states. Furthermore, the effects of ambient gases on the band structure and on the loss function have been probed

Oxidized multiwalled nanotubes as efficient carbocatalyst for the general synthesis of azines

The carbocatalytic synthesis of azines (N-N linked diimines) by mild-oxidized multiwalled carbon nanotubes catalyst (oxMWNT) is presented. The material, just with a 5 %wt. loading, is able to carry out a smooth room-temperature metal-free condensation of aldehydes and hydrazine, without external additives, to obtain a wide library of symmetric and also asymmetric azines in excellent yields, even in gram scale, with an excellent selectivity for aromatic substrates. This methodology allows the synthesis of azines with application in nonlinear optics, and the organic materials and biological active compounds crafting. oxMWNT catalysed the reaction in just 3 h with full recyclability upon the recovery of the catalyst. In addition, due to the inherent oxMWNT oxidative capacity in the presence of nitric acid, we have also developed the one-pot synthesis of azines starting from alcoholsFinancial support was provided by the European Research Council (ERC-CoG, Contract Number: 647550, ERC-PoC, Contract No. 861930), the Spanish Government (RTI2018-095038-B-I00), the ‘Comunidad de Madrid’ and European Structural Funds (S2018/NMT-4367) and proyectos sinérgicos I+D (Y2020/NMT6469). M.B. wishes to thank the Spanish Government for a Juan de la Cierva contract (IJC2019-042157-I

Multimodal hybrid 2D networks via the thiol-epoxide reaction on 1T/2H MoS2 polytypes

The study adds a fundamental tile to the still incomplete puzzle of covalent functionalization tools of 2D inorganic networks and describes a protocol where organic moieties are covalently grafted at both phases (1T and 2H) of a CE-MoS2 sample