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[EN]The project addresses the topic of reclassifying an urban area of the city of Livorno caracterised by the presence of the Forte San Pietro and the Rivellino di San Marco built at the end of the 17th century to complete Livorno’s northern defensive front protecting the residential quarter of La Venezia. In particular, Forte San Pietro, constructed on the orders of Governor Dal Borro according to the designs of the architect, Baldi, surrounded on one side by the sea and on the other by the Fosso Reale, it was the site of the public slaughterhouse (which was in operation until 1996) from 1889 and this saved it from demolition in the following years, ensuring links with the nearby San Marco’s station and free land for the city’s expansion. This transformed the Rivellino, which was the object of a residential development plan in the early 1800s and the location of the city’s sewage treatment plant. The project area is located in the north-west of the municipal region of Livorno and is configured as a passage area, in which the city environment abruptly changes from the industrial port to the urban and where traces of the ancient fortifications are evident (in addition to Forte San Pietro there are the constituent parts of the Lorenesi city walls) and where a system of canals and cellars is testimony to this particular area of the city’s characteristic special relationship with water. The study was initially focused on the analysis (historical, functional and regulatory) of the regional context so that the characteristic elements of the area being studied were clear and this enabled the objectives to be pursued in the masterplan to be identified.

Rechargeable aqueous Zn-ion batteries (ZIBs) have obtained extensive attention owing to their high safety, low-cost, environmental friendliness and high energy density. Nevertheless, developing suitable cathode materials remains challenging due to requirements for appropriate microstructure. We present a porous N-doped carbon nanosheet/MnO2 (NCS/MnO2) derived from bacterial cellulose (BC) by a simple route. BC chunks were soaked in urea solution and then carbonized under Ar flow at 900 °C. N-doped carbon nanosheets were obtained and MnO2 was added by reaction with NaMnO4. Benefiting from both the conductivity and porosity of the NCS support, the NCS/MnO2 composite delivers a high capacity and long cycling stability (114 mA h g−1 at 2 A g−1 after 1800 cycles). The electrode reaction mechanism was further investigated and the MnO2 dissolution/deposition mechanism was confirmed, with a critical role of zinc sulfate hydroxide (ZSH) to assist the deposition of MnO2

Synchrotron radiation based techniques are powerful tools for battery research and allow probing a wide range of length scales, with different depth sensitivities and spatial/temporal resolutions. Operando experiments enable characterization during functioning of the cell and are thus a precious tool to elucidate the reaction mechanisms taking place. In this perspective, the current state of the art for the most relevant techniques (scattering, spectroscopy, and imaging) is discussed together with the bottlenecks to address, either specific for application in the battery field or more generic. The former includes the improvement of cell designs, multi-modal characterization and development of protocols for automated or at least semi-automated data analysis to quickly process the huge amount of data resulting from operando experiments. Given the recent evolution in these areas, accelerated progress is expected in the years to come, which should in turn foster battery performance improvements.

The reversible and irreversible cationic and anionic charge compensation mechanisms occurring along the first charge and discharge cycle of Li- and Mn-rich Li[Li0.2Ni0.16Mn0.56Co0.08]O2 cathode material at (dis)charge rates of 0.1C and 5C have been identified and quantified by X-ray absorption and emission spectroscopy. The analysis provided the oxidation states of the transition metals, the Mn local coordination, and the lattice elastic constants. Lattice softening occurs along the first charge, while a minor spinel phase forms irreversibly at the expense of the layered phase. Higher charge rate increases the spinel formation and induces an increased softening in the delithiated lattice, which is expected to correspond to a reduced reversible anionic redox. The results evidence a comparable cationic and anionic oxidation since the beginning of the charge, while only anions are contributing towards its end, equivalent to roughly 10% of structural oxygen irreversibly lost. Higher charge rates resulted in a decreased reversible anionic redox, anticipating the cationic oxidation. The reported results provide a reliable experimental approach to characterize the key parameters controlling the reversible and irreversible cationic and anionic contributions to the charge compensation mechanism.

[EN] The rational design and in deep understanding of efficient, affordable and stable materials to promote the light-assisted production of fuels and commodity chemicals is very appealing for energy crisis and climate change amelioration. Herein, we have prepared a series of Co-doped hydroxyapatite (HAP) catalysts with different Co content. The materials structure has been widely investigated by XRD, FT-IR, HRTEM, XPS, XAS, as well as computational simulations based on Density Functional Theory (DFT) with PBE functional. At low Co loading, there is a partial substitution of Ca cations in the HAP structure, while higher loadings promote the precipitation of small (similar to 2 nm) Co nanoparticles on the HAP surface. For the optimal Co content, a constant CO rate of 62 mmol center dot g(-1)center dot h(-1) at 1 sun illumination and 400 degrees C, with the material being stable for 90 h. Visible and NIR photons have been determined responsible of the light-assisted activity enhanced. Mechanistic studies based on both experimental and DFT simulations show that H-2 preferentially adsorbs to metallic Co, while CO2 adsorbs to the HAP surface oxygen. Moreover, both direct photo- and plasmon-driven contributions have been separated in order to study their mechanisms independently.

The generation of methane fuel using surplus renewable energy with CO as the carbon source enables both the decarbonization and substitution of fossil fuel feedstocks. However, high temperatures are usually required for the efficient activation of CO. Here we present a solid catalyst synthesized using a mild, green hydrothermal synthesis that involves interstitial carbon doped into ruthenium oxide, which enables the stabilization of Ru cations in a low oxidation state and a ruthenium oxycarbonate phase to form. The catalyst shows an activity and selectivity for the conversion of CO into methane at lower temperatures than those of conventional catalysts, with an excellent long-term stability. Furthermore, this catalyst is able to operate under intermittent power supply conditions, which couples very well with electricity production systems based on renewable energies. The structure of the catalyst and the nature of the ruthenium species were acutely characterized by combining advanced imaging and spectroscopic tools at the macro and atomic scales, which highlighted the low-oxidation-state Ru sites (Ru, 0 < n < 4) as responsible for the high catalytic activity. This catalyst suggests alternative perspectives for materials design using interstitial dopants.

The rational design and in deep understanding of efficient, affordable and stable materials to promote the light-assisted production of fuels and commodity chemicals is very appealing for energy crisis and climate change amelioration. Herein, we have prepared a series of Co-doped hydroxyapatite (HAP) catalysts with different Co content. The materials structure has been widely investigated by XRD, FT-IR, HRTEM, XPS, XAS, as well as computational simulations based on Density Functional Theory (DFT) with PBE functional. At low Co loading, there is a partial substitution of Ca cations in the HAP structure, while higher loadings promote the precipitation of small (∼ 2 nm) Co nanoparticles on the HAP surface. For the optimal Co content, a constant CO rate of 62 mmol·g·h at 1 sun illumination and 400 °C, with the material being stable for 90 h. Visible and NIR photons have been determined responsible of the light-assisted activity enhanced. Mechanistic studies based on both experimental and DFT simulations show that H preferentially adsorbs to metallic Co, while CO adsorbs to the HAP surface oxygen. Moreover, both direct photo- and plasmon-driven contributions have been separated in order to study their mechanisms independently.

Zeolites containing Rh single sites stabilized by phosphorous were prepared through a one-pot synthesis method and are shown to have superior activity and selectivity for ethylene hydroformylation at low temperature (50 °C). Catalytic activity is ascribed to confined RhO clusters in the zeolite which evolve under reaction conditions into single Rh sites. These Rh sites are effectively stabilized in a Rh-(O)-P structure by using tetraethylphosphonium hydroxide as a template, which generates in situ phosphate species after H activation. In contrast to RhO, confined Rh clusters appear less active in propanal production and ultimately transform into Rh(I)(CO) under similar reaction conditions. As a result, we show that it is possible to reduce the temperature of ethylene hydroformylation with a solid catalyst down to 50 °C, with good activity and high selectivity, by controlling the electronic and morphological properties of Rh species and the reaction conditions.