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Lithium-ion batteries (LIBs) are a widely used energy storage technology as they possess high energy density and are characterized by the reversible intercalation/deintercalation of Li ions between electrodes. The rapid development of LIBs has led to increased production efficiency and lower costs for manufacturers, resulting in a growing demand for batteries and their application across various industries, particularly in different types of vehicles. In order to meet the demand for LIBs while minimizing climate-impacting emissions, the reuse, recycling, and repurposing of LIBs is a critical step toward achieving a sustainable battery economy. This paper provides a comprehensive review of lithium-ion battery recycling, covering topics such as current recycling technologies, technological advancements, policy gaps, design strategies, funding for pilot projects, and a comprehensive strategy for battery recycling. Additionally, this paper emphasizes the challenges associated with developing LIB recycling and the opportunities arising from these challenges, such as the potential for innovation and the creation of a more sustainable and circular economy. The environmental implications of LIB recycling are also evaluated with methodologies able to provide a sustainability analysis of the selected technology. This paper aims to enhance the comprehension of these trade-offs and encourage discussion on determining the “best” recycling route when targets are in conflict.

This review discusses the techniques available for detecting and inactivating of pathogens in municipal wastewater, landfill leachate, and solid waste. In view of the current COVID-19 pandemic, SARS-CoV-2 is being given special attention, with a thorough examination of all possible transmission pathways linked to the selected waste matrices. Despite the lack of works focused on landfill leachate, a systematic review method, based on cluster analysis, allows to analyze the available papers devoted to sewage sludge and wastewater, allowing to focalize the work on technologies able to detect and treat pathogens. In this work, great attention is also devoted to infectivity and transmission mechanisms of SARS-CoV-2. Moreover, the literature analysis shows that sewage sludge and landfill leachate seem to have a remote chance to act as a virus transmission route (pollution-to-human transmission) due to improper collection and treatment of municipal wastewater and solid waste. However due to the incertitude about virus infectivity, these possibilities cannot be excluded and need further investigation. As a conclusion, this paper shows that additional research is required not only on the coronavirus-specific disinfection, but also the regular surveillance or monitoring of viral loads in sewage sludge, wastewater, and landfill leachate. The disinfection strategies need to be optimized in terms of dosage and potential adverse impacts like antimicrobial resistance, among many other factors. Finally, the presence of SARS-CoV-2 and other pathogenic microorganisms in sewage sludge, wastewater, and landfill leachate can hamper the possibility to ensure safe water and public health in economically marginalized countries and hinder the realization of the United Nations' sustainable development goals (SDGs).

This review discusses the techniques available for detecting and inactivating of pathogens in municipal wastewater, landfill leachate, and solid waste. In view of the current COVID-19 pandemic, SARS-CoV-2 is being given special attention, with a thorough examination of all possible transmission pathways linked to the selected waste matrices. Despite the lack of works focused on landfill leachate, a systematic review method, based on cluster analysis, allows to analyze the available papers devoted to sewage sludge and wastewater, allowing to focalize the work on technologies able to detect and treat pathogens. In this work, great attention is also devoted to infectivity and transmission mechanisms of SARS-CoV-2. Moreover, the literature analysis shows that sewage sludge and landfill leachate seem to have a remote chance to act as a virus transmission route (pollution-to-human transmission) due to improper collection and treatment of municipal wastewater and solid waste. However due to the incertitude about virus infectivity, these possibilities cannot be excluded and need further investigation. As a conclusion, this paper shows that additional research is required not only on the coronavirus-specific disinfection, but also the regular surveillance or monitoring of viral loads in sewage sludge, wastewater, and landfill leachate. The disinfection strategies need to be optimized in terms of dosage and potential adverse impacts like antimicrobial resistance, among many other factors. Finally, the presence of SARS-CoV-2 and other pathogenic microorganisms in sewage sludge, wastewater, and landfill leachate can hamper the possibility to ensure safe water and public health in economically marginalized countries and hinder the realization of the United Nations' sustainable development goals (SDGs).

This paper highlights advantages and drawbacks due to the use of portable and low-cost devices for aerosol sampling, showing their performances during an aerosol monitoring campaign with the parallel use of the gravimetric sampling reference method and a cascade impactor. A specific monitoring campaign was held running all instruments in parallel in indoor, confined, and outdoor environments characterized by local emission sources or particulate matter background concentra-tions. PM2.5 concentrations were used to compare data emerging from the different instruments adopted. Significant underestimation of PM2.5 emerged when comparing data coming from optical sensors with those estimated by the cascade impactor, whose data resulted in being coherent with gravimetric determination, integrated over the same sampling time. A cause–effect relationship between PM2.5 concentrations and specific emission sources was found when observing the daily patterns of all the real-time sampling devices. It emerged that optical devices are useful for detecting concentration trends, the presence of peak values, or changes in the background value, even if with limited accuracy and precision. The comparison with particle size distributions obtained by the cascade impactor data allowed us to define which particle sizes are not detected by different optical devices, evidencing a low representativeness of optical low-cost sensors for health exposure measurements. The correlations among the specific particle size fractions detected by the cascade im-pactor and their specific emission sources were particularly high for car emissions in a semi-confined garage area.

This study investigates the effect of technologies for heavy metal stabilization on the concentration of PolyChlorinatedDibenzo-p-Dioxins (PCDD) and PolyChlorinatedDibenzoFurans (PCDF), abbreviated PCDD/F, in Municipal Solid Waste Incineration (MSWI) fly ash. We determined the variation of the Total Organic Carbon (TOC) and PCDD/F concentration between raw and stabilized material. The technologies, that already proved to be very promising for heavy metal entrapment, showed encouraging results also for PCDD/F detoxification. This result could be very impacting on the management of MSWI fly ash: at the best of our knowledge, there are no methods, in literature, that can provide good results in stabilization of heavy metals, and abatement of chlorinated organic pollutants contained in the same matrix.

This study investigates the effect of technologies for heavy metal stabilization on the concentration of PolyChlorinatedDibenzo-p-Dioxins (PCDD) and PolyChlorinatedDibenzoFurans (PCDF), abbreviated PCDD/F, in Municipal Solid Waste Incineration (MSWI) fly ash. We determined the variation of the Total Organic Carbon (TOC) and PCDD/F concentration between raw and stabilized material. The technologies, that already proved to be very promising for heavy metal entrapment, showed encouraging results also for PCDD/F detoxification. This result could be very impacting on the management of MSWI fly ash: at the best of our knowledge, there are no methods, in literature, that can provide good results in stabilization of heavy metals, and abatement of chlorinated organic pollutants contained in the same matrix.

An engineered multilayer structure of platinum-cadmium stannate-titanium oxide (Pt-CTO-TO), with different TO layer thickness (in the range 1-5 nm), has been grown at 400 °C on glass substrates by RF magnetron sputtering, following a 2-step procedure without breaking vacuum. To produce an alternative and reliable front contact for dye sensitized solar cells (DSCs), morphology and composition of a TO blocking layer have been studied, paying particular attention to the oxide-oxide (CTO-TO) interface characteristics. The influence of the metallic mesh on the transparent conductive oxide sheet resistance has also been considered. A sputtered CTO layer shows a high average transmittance, over 90%. The Pt mesh yields a drastic reduction in the series resistance, almost one order, without affecting the optical properties. The ultrathin blocking layer of Ti oxide prevents charge recombination, improving the overall performance of the solar cells: +86% in efficiency, +50% in short circuit current, with respect to bare CTO.

Nanostructured (3-6 nm) thin films (80 nm) of SnO2 and Pt-doped SnO2 were obtained by a new sol-gel route using tetra(tert-butoxy)tin(IV) and bis(acetylacetonato)platinum(II) as precursors. EPR and XPS investigations, performed on thin films after interaction with CO, demonstrated that singly ionized oxygen vacancies (V-o(.)) fully transferred their electrons to the noble metal and reduced Pt(IV) to Pt(ll). Contact with air at room temperature led to the reduction of O-2 to O-2(-), therefore, re-oxidizing metal centers. The reaction mechanism concords with the high electrical sensitivity of this material. (C) 2001 Elsevier Science B.V. All rights reserved.

Nanostructured (3-6 nm) thin films (80 nm) of SnO2 and Pt-doped SnO2 were obtained by a new sol-gel route using tetra(tert-butoxy)tin(IV) and bis(acetylacetonato)platinum(II) as metal precursors. The results of glancing incidence X-ray diffraction (GIXRD) and X-ray photoelectron spectroscopy (XPS) investigations demonstrated that platinum substituted for tin(IV) in the cassiterite structure. Electron paramagnetic resonance (EPR) and XPS analyses showed that singly ionized paramagnetic oxygen vacancies (Vo(.)) were formed on pure SnO2 thin films by interaction with CO atmosphere; in Pt-doped SnO2 films, the same defects Vo(.) fully transferred their electrons to the noble metal so that Pt(IV) became Pt(II) and Pt(0). Such samples successively exposed to air, at room temperature, reduced O-2 to O-2(-). The behavior was well-detected by EPR measurements, which showed on thin films the presence of Sn(IV)-O-2(-) species. The surface reactivity agrees with the results of the electrical measurements.

Pt/alpha-Fe2O3 nanocomposites were synthesized on fluorine-doped tin oxide (FTO) substrates by a sequential plasma enhanced-chemical vapor deposition (PE-CVD)/radio frequency (RF) sputtering approach, tailoring the overall Pt content as a function of sputtering time. The chemico-physical properties of the as-prepared systems were extensively investigated by means of complementary techniques, including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission-scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDXS), secondary ion mass spectrometry (SIMS), and optical absorption spectroscopy, and compared to those of the homologous Pt/alpha-Fe2O3 systems annealed in air prior and/or after sputtering. The obtained results evidenced that the material compositional, structural and morphological features, with particular regard to the Pt oxidation state and hematite nano-organization, could be finely tailored as a function of the adopted processing conditions. Pt/alpha-Fe2O3 systems were finally tested as photoanodes in photoelectrochemical (PEC) water splitting experiments, evidencing a remarkable interplay between functional performances and the above-mentioned material properties, as also testified by transient absorption spectroscopy (TAS) results.

Pt/alpha-Fe2O3 nanocomposites were synthesized on fluorine-doped tin oxide (FTO) substrates by a sequential plasma enhanced-chemical vapor deposition (PE-CVD)/radio frequency (RF) sputtering approach, tailoring the overall Pt content as a function of sputtering time. The chemico-physical properties of the as-prepared systems were extensively investigated by means of complementary techniques, including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission-scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDXS), secondary ion mass spectrometry (SIMS), and optical absorption spectroscopy, and compared to those of the homologous Pt/alpha-Fe2O3 systems annealed in air prior and/or after sputtering. The obtained results evidenced that the material compositional, structural and morphological features, with particular regard to the Pt oxidation state and hematite nano-organization, could be finely tailored as a function of the adopted processing conditions. Pt/alpha-Fe2O3 systems were finally tested as photoanodes in photoelectrochemical (PEC) water splitting experiments, evidencing a remarkable interplay between functional performances and the above-mentioned material properties, as also testified by transient absorption spectroscopy (TAS) results.

An engineered multilayer structure of platinum-cadmium stannate-titanium oxide (Pt-CTO-TO), with different TO layer thickness (in the range 1-5 nm), has been grown at 400 °C on glass substrates by RF magnetron sputtering, following a 2-step procedure without breaking vacuum. To produce an alternative and reliable front contact for dye sensitized solar cells (DSCs), morphology and composition of a TO blocking layer have been studied, paying particular attention to the oxide-oxide (CTO-TO) interface characteristics. The influence of the metallic mesh on the transparent conductive oxide sheet resistance has also been considered. A sputtered CTO layer shows a high average transmittance, over 90%. The Pt mesh yields a drastic reduction in the series resistance, almost one order, without affecting the optical properties. The ultrathin blocking layer of Ti oxide prevents charge recombination, improving the overall performance of the solar cells: +86% in efficiency, +50% in short circuit current, with respect to bare CTO. © 2013 The Owner Societies.

The distribution of arsenic (As) in the soil, rice grain and straw of Kaudikasa, Rajnandgaon, central India is described. Speciation of monomethylarsenonate (MMA) and dimethylarsinite (DMA) and As(III) in the rice grain is presented. A remarkably high concentration of arsenic in soil is observed. The geogenic sources of arsenic and other metals in the soil were apportioned., QC 20130130

A very large surface to volume ratio of nanoporous silicon (PS) produces a high density of surface states, which are responsible for uncontrolled oxidation of the PS surface. Hence it disturbs the stability of the material and also creates difficulties in the formation of a reliable electrical contact. To passivate the surface states of the nanoporous silicon, noble metals (Pd, Ru, and Pt) were dispersed on the PS surface by an electroless chemical method. GIXRD (glancing incidence X-ray diffraction) proved the crystallinity of PS and the presence of noble metals on its surface. While FESEM (field emission scanning electron microscopy) showed the morphology, the EDX (energy dispersive X-ray) line scans and digital X-ray image mapping indicated the formation of the noble metal islands on the PS surface. Dynamic SIMS (secondary ion mass spectroscopy) further confirmed the presence of noble metals and other impurities near the surface of the modified PS. The variation of the surface roughness after the noble metal modification was exhibited by AFM (atomic force microscopy). The formation of a thin oxide layer on the modified PS surface was verified by XPS (X-ray photoelectron spectroscopy).

SiO2 ultrathin and thin films have been deposited on single-crystal Si substrates by means of nonreactive radio frequency magnetron sputtering. The temperature of the substrate and the deposition times have been varied in the range of 200-500 degrees C and 60-14 400 s, respectively. The average deposition rate has a range of 0.5-5 nm/min and tends to decrease with the increase of the substrate temperature. Two different growth regimes may be observed for ultrathin and thin films, the transition taking place in the range of 5-10 nm depending on the substrate temperature. The roughness of the film surface and the grain dimensions do increase with the substrate temperature for short deposition times (t <= 300 s), whereas their behavior is less defined for intermediate ones (300 s < t < 1800 s). Finally, for long deposition times (t > 1800 s) the roughness increases again with T, and its slope is higher, the higher the substrate temperature is

The thermal evolution of sol-gel SnO2-based thin films was explored by investigating their structural and morphological features. Nanostructured SnO2 and Pt-doped SnO2 layers were obtained using tetra(tert-butoxy)tin(IV) and Pt(II) acetlylacetonate as precursors. Films were prepared by spin coating from ethanol solutions with different viscosity. After drying at room temperature, they were annealed in air at 673 and 973 K. The surface morphology was analyzed by scanning electron microscopy, atomic force microscopy, and scanning near-field optical microscopy. The structural characterization was performed by means of glancing incidence X-ray diffraction and microdiffraction. Both drying at room temperature and thermal treatment at 673 K resulted in the formation of holes on the surface and inside the films. Their distribution and average dimension were found to depend mainly on the viscosity of the sol precursor, and on the presence of Pt in the films. After annealing at 973 K, surface segregation of PtOx phases and partial filling of the surface holes occurred. The effects of morphology on the electrical transport properties are discussed on the basis of sensitivity, S, measurements (S = Rair/RCO where Rair and RCO stand for the resistance in air and CO/air, respectively).

The correlations between structure and magnetism in [Co(0.9 nm)/Au(5 nm)]XN multilayer films with different number of repetitions N510, 30, and 50, have been studied by the combined use of complementary structural and magnetic techniques, such as x-ray reflectivity, x-ray diffraction, and transmission electron microscopy, alternating gradient force magnetometry, magnetic force microscopy and Brillouin light scattering. On increasing the value of N, an overall improvement of the multilayer quality is observed which corresponds to a change in the micromagnetic structure and to an enhancement of the perpendicular anisotropy. These effects have been attributed to a reduction of the magnetostatic energy associated with the formation of perpendicular magnetic domains in multilayers with increasing number of layers repetitions.

Paramagnetic singly ionized oxygen vacancies V0and chemisorbed Sn4+-O2- species were detected by electron paramagnetic resonance measurements on SnO2 and transition metal (Pt, Ru)-doped SnO2 thin film that had been reduced with CO at different temperatures and then brought into contact with oxygen. The amounts of the two paramagnetic species were evaluated and are discussed as a function of the film annealing temperature in air, the reduction temperature under CO, and the type and concentration of the doping transition element. Also the structural properties of the film were identified through glancing incidence X-ray diffraction analysis. Measurements of the electrical sensitivity S (S = Rair/RCO, where Rair and RCO are the resistance under air and under CO(800 ppm)/air respectively) show the trend of the sensitivity values vs. the reduction temperature with CO could be predicted by the parallel trend of the number of Sn4+-O2- centers.

Dark metamorphic stone has traditionally been employed for decorative purposes and for architectural cladding, but after prolonged outdoor exposure the characteristic surface colour tends to fade. Oira stone, a durable lithotype belonging to the ultramafic rock group, was employed during the 19th century restoration of the Renaissance facade of the cathedral in Monza, Italy, and the features and conservation state of the stone were studied following more than a century of exposure as part of a pilot conservation project. A marked discolouration characterised by diffuse fading of the typical intense dark colour of Oira stone was observed on all exposed surfaces of the facade, irrespective of its location. The formation of a fragile superficial layer with scaling and detachment was also observed. Analysis of samples of the stone showed that the colour variation is associated with chemical alteration, resulting in selective leaching of Mg ions from the phyllosilicate microstructure of the mineral lizardite to a depth of about 500 micrometres. Simultaneous surface recrystallisation of mainly low-order SiO2 also occurred. Accelerated laboratory ageing tests were also conducted on representative serpentinite samples which provided comparable results in relation to colour alteration, but with less intense increase in lightness., Dark metamorphic stone has traditionally been employed for decorative purposes and for architectural cladding, but after prolonged outdoor exposure the characteristic surface colour tends to fade. Oira stone, a durable lithotype belonging to the ultramafic rock group, was employed during the 19th century restoration of the Renaissance facade of the cathedral in Monza, Italy, and the features and conservation state of the stone were studied following more than a century of exposure as part of a pilot conservation project. A marked discolouration characterised by diffuse fading of the typical intense dark colour of Oira stone was observed on all exposed surfaces of the facade, irrespective of its location. The formation of a fragile superficial layer with scaling and detachment was also observed. Analysis of samples of the stone showed that the colour variation is associated with chemical alteration, resulting in selective leaching of Mg ions from the phyllosilicate microstructure of the mineral lizardite to a depth of about 500 micrometres. Simultaneous surface recrystallisation of mainly low-order SiO2 also occurred. Accelerated laboratory ageing tests were also conducted on representative serpentinite samples which provided comparable results in relation to colour alteration, but with less intense increase in lightness.