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Composite polymer electrolytes are systems of choice for future solid-state lithium metal batteries (LMBs). Poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) is among the most interesting matrices to develop new generation quasi-solid electrolytes (QSEs). Here it is reported on nanocomposites made of PVDF-HFP and pegylated SiO2 nanoparticles. Silica-based hybrid nanofillers are obtained by grafting chains of poly(ethylene glycol) methyl ether (PEG) with different molecular weight on the surface of silica nanoparticles. The functionalized nanofiller improves the mechanical, transport and electrochemical properties of the QSEs, which show good ionic conductivity values and high resistance against dendrite penetration, ensuring boosted long and safe device operation. The most promising result is obtained by dispersing 5 wt% of SiO2 functionalized with short PEG chains (PEG750, Mw = 750 g mol−1) in the PVDF-HFP matrix with an ease solvent-casting procedure. It shows ionic conductivity of 0.1 mS cm−1 at 25 °C, more than 250 h resistance to stripping/plating, and impressive results during cycling tests in LMB with LiFePO4 cathode.

We are all users of lithium-ion batteries (LIBs), the electrochemical energy storage devices that revolutionized our life, making the diffusion of portable and wearable devices possible and now driving the switch from a combustion engine to electric vehicles in the transportation sector. These positive trends are however leading to two whiplash effects: the issue related to management of LIBs when they reach the end of their life (EoL-LIBs) and the supply of the critical raw materials (CRMs) needed to produce the essential LIBs’ components. Recycling of EoL-LIBs is the answer to these two problems, addressing the aspects of waste management while providing a secondary source of CRMs needed to produce new LIBs, in a closed-loop circular economy scheme. The proposed laboratory activity is specifically focused on the recycling of LiCoO2, the most diffused cathode material and also the one containing the highest amount of CRMs. The students will be called to analyze the degradation procedure through acidic leaching, comparing the method today mostly exploited at industrial level (using inorganic acid) and the method recently proposed in the scientific literature (exploiting organic acids). Students will be called to consider not only quantitative chemical indicators (yields of degradation and recovery of CRMs) but also the cost, safety, and disposal of the procedure. The aim of this experience is to drive the students to critically consider all aspects related to sustainability, to present them the tools to quantitatively assess it, and to create awareness regarding a technology involved in our everyday life.

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.

ithium-ion batteries (LIBs) are at the forefront of electrochemical energy storage both for consumer electronics, and for power/energy more demanding applications, such as in automotive and grid levelling. However, their chemical and electrochemical stability must be further improved. Among the instability causes, a major role is played by residual moisture. As a matter of fact, hydrofluoric acid generated by hydrolysis of LiPF6, the most common lithium salt in LIBs, causes safety issues and performance losses. Here we demonstrate the scavenging properties vs. HF of a barium silicate glass used as a filler in a PVDF-HFP based gel polymer electrolyte. A full LiTi2(PO4)3|electrolyte|LiMn2O4 cell is stable for 200 cycles at 0.1C.

The current historical period can be considered a golden age for Lithium-Ion Batteries (LIBs), which accompany our lives from portable devices (e.g. cell phones) to electric vehicles. Unfortunately, the scarsity and univen distribution of some of the raw materials that are mandatory for LIBs' manufacturing means that the growth of this market is threatened. To alleviate this problem, Sodium-Ion Batteries (NIBs) can be introduced to partially substitute LIBs. Some research on new categories of electrode materials is however required to improve NIBs. The research presented here focuses on Nb-based NASICON materials for Sodium-Ion Batteries. As an example, two new phases are proposed: NaFeNb(PO4)3 and NaAlNb(PO4)3. After a facile and reproducible synthesis, the two phases have been studied electrochemically and via operando XAS and XRD, revealing the reaction's kinetics upon sodiation and desodiation.

Batteries are electrochemical devices that have characterized society and its development in recent decades. Moreover, to improve the use of renewable energy sources and electric vehicles, and with the continuous growth of the demand for portable electronics, the demand for batteries that can meet global needs has increased. Currently, the most widely used type of them is the lithium-ion battery (LIB), which is reliable and provides satisfying electrochemical performances[1]. However, the most used anode in this system is the graphite anode (theoretical capacity of 370 mAh g-1), which suffers from aging and becomes unsafe with high currents. So, it is important to investigate other types of materials as possible and promise anode that could give better properties. MAX phase (where M is a transition metal cation, A is a metallic or metalloid element and X is C, N or B) are a class of 3D materials, with layered hexagonal crystal structure (space group P63/mmc) consisting of several layers of MX, alternated with layers of pure A-elements along the c cell parameter[2]. One of the most common of this class of materials is the Ti3AlC2 MAX phase. However, it shows poor energy storage performances as active electrode (capacity of 60 mAh g-1). One compound well-known as active material is titanium oxide (TiO2). This has been shown to be a well-established and particularly stable material for applications in ion batteries. However, it has a lower capacity than graphite[3]. One interesting material as electrode is tin oxide (SnO2): this is a very promising material due to its high specific capacity, but it suffers from poor stability due to the high volume change it undergoes during charge and discharge cycles[4]. A possible strategy to improve the long-term stability of this oxide is to use the stable titanium oxide with it: is reported that by adding it, making a solid solution of Sn/Ti oxide, the total system achieves less volume change during cycling and so gains a stabili

Batteries are electrochemical devices that have characterized society and its development in recent decades. Moreover, to improve the use of renewable energy sources and electric vehicles, and with the continuous growth of the demand for portable electronics, the demand for batteries that can meet global needs has increased. Currently, the most widely used type of them is the lithium-ion battery (LIB), which is reliable and provides satisfying electrochemical performances. However, the most used anode in this system is the graphite anode (theoretical capacity of 370 mAh g-1 ), which suffers from aging and becomes unsafe with high currents. So, it is important to investigate other types of materials as possible and promise anode that could give better properties. MAX phase (where M is a transition metal cation, A is a metallic or metalloid element and X is C, N or B) are a class of 3D materials, with layered hexagonal crystal structure (space group P63/mmc) consisting of several layers of MX, alternated with layers of pure A-elements along the c cell parameter. One of the most common of this class of materials is the Ti3AlC2 MAX phase. However, it shows poor energy storage performances as active electrode (capacity of 60 mAh g-1). One compound well-known as active material is titanium oxide (TiO2). This has been shown to be a well-established and particularly stable material for applications in ion batteries. However, it has a lower capacity than graphite. One interesting material as electrode is tin oxide (SnO2): this is a very promising material due to its high specific capacity, but it suffers from poor stability due to the high volume change it undergoes during charge and discharge cycles. A possible strategy to improve the long-term stability of this oxide is to use the stable titanium oxide with it: is reported that by adding it, making a solid solution of Sn/Ti oxide, the total system achieves less volume change during cycling and so gains a stability improvem

Lithium-ion batteries are constantly developing as the demands for power and energy storage increase. One promising approach to designing high-performance lithium-ion batteries is using conversion/alloying materials, such as SnO2. This class of materials does, in fact, present excellent performance and ease of preparation; however, it suffers from mechanical instabilities during cycling that impair its use. One way to overcome these problems is to prepare composites with bi-dimensional materials that stabilize them. Thus, over the past 10 years, two-dimensional materials with excellent transport properties (graphene, MXenes) have been developed that can be used synergistically with conversion materials to exploit both advantages. In this work, a 50/50 (by mass) SnO2/Ti3C2Tz nanocomposite is prepared and optimized as a negative electrode for lithium-ion batteries. The nanocomposite delivers over 500 mAh g−1 for 700 cycles at 0.1 A g−1 and demonstrates excellent rate capability, with 340 mAh g−1 at 8 A g−1. These results are due to the synergistic behavior of the two components of the nanocomposite, as demonstrated by ex situ chemical, structural, and morphological analyses. This knowledge allows, for the first time, to formulate a reaction mechanism with lithium-ions that provides partial reversibility of the conversion reaction with the formation of SnO.

A novel route for the valorization of waste into valuable products was developed. Surgical masks commonly used for COVID 19 protection by stopping aerosol and droplets have been widely used, and their disposal is critical and often not properly pursued. This work intended to transform surgical masks into platinum group metal-free electrocatalysts for oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER) as well as into crude oil. Surgical masks were subjected to controlled-temperature and -atmosphere pyrolysis, and the produced char was then converted into electrocatalysts by functionalizing it with metal phthalocyanine of interest. The electrocatalytic performance characterization towards ORR and HER was carried out highlighting promising activity. At different temperatures, condensable oil fractions were acquired and thoroughly analyzed. Transformation of waste surgical masks into electrocatalysts and crude oil can open new routes for the conversion of waste into valuable products within the core of the circular economy.

Making a consistency with the objectives of circular economy, herein, waste pistachios shells were utilized for the development of hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR) electrocatalysts which are the key bottleneck in the technological evolution of electrolyzers and fuel cells, respectively. As an alternative to scarce and expensive platinum-group-metal (PGM) electrocatalysts, metal nitrogen carbons (MNCs) are emerging as a promising candidate for both aforementioned electrocatalysis where iron and nickel are the metal of choice for ORR and HER, respectively. Therefore, FeNCs and NiNCs were fabricated utilizing inedible pistachio shells as a low-cost biosource of carbon. The steps involved in the fabrication of electrocatalyst were correlated with electrochemical performance in alkaline media. Encouraging onset potential of ~ 0.88 V vs RHE with a possibility of a 2 + 2 reaction pathway was observed in pyrolyzed and ball-milled FeNC. However, HF etching for template removal slightly affected the kinetics and eventually resulted in a relatively higher yield of peroxide. In parallel, the pyrolyzed NiNC demonstrated a lower HER overpotential of ~ 0.4 V vs RHE at − 10 mA cm−2. Nevertheless, acid washing adversely affected the HER performance and consequently, very high overpotential was witnessed.

MXenes are an emerging class of materials considered for many applications, such as sensors, catalysis, energy storage devices. The main obstacle towards their massive implementation is the synthesis requiring the direct use of HF as etching agent. The development of alternative synthetic routes exploiting in-situ forming HF agents is the main strategies to overcome this limitation. In this study four different etching methods based on the use of NH4HF2, NaF−HCl, HBF4, and NaBF4−HCl are compared to produce Ti3C2Tx from Ti3AlC2 towards the application of MXenes in sodium ion batteries. Three of such etching methods have already been reported while one is here presented for the first time. The structural analysis of the obtained products is based on X-ray diffraction (XRD), scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX), and X-ray photoelectron spectroscopy (XPS) analysis. All the materials have been tested in half-cell configuration vs. Na; the charge/discharge profiles and the C-rate tests are discussed and related to specific structural features. Overall, the results reveal that the MXene obtained using the HBF4 etching agent under mild conditions is comparable both in structure and functional properties to the benchmark material, i. e., the MXene produced using HF at 5 % concentration. Indeed, the MXene synthetized with the HBF4 presents the lowest mean voltage and potential hysteresis and shows the highest first cycle efficiency (69.7 %), overcoming the performance of the MXene produced with 5 % HF (67 %). This study proves the possibility to produce MXene with a more sustainable route.

Pyrophosphates of the general formula A2BP2O7 (A = alkali metal and B = transition metal) find applications in several technological fields, including rechargeable Na-ion batteries. They present a rich polymorphism vs composition, which may strongly influence their functional properties. Therefore, to selectively obtain a specific structure is crucial for applications. Here, we combine structural investigation techniques (solid-state NMR, X-ray and neutron diffraction, and DFT calculations) to investigate the crystal chemistry of the series Na2(M/M’)P2O7 with couples M/M’ = Co/Zn and Co/Fe. For both the series, a phase transition vs composition is observed. A tetragonal to orthorhombic phase transition is found for the Zn/Co series, and an orthorhombic to triclinic phase transition is found for the Co/Fe series. Such changes are interpreted in view of the different electronic structures of the transition metal ion. In addition, with the support of modeling, short- and long-range structural analysis, we show that the coexistence of two polymorphs for a given composition is possible, suggesting that the final structures may be strongly dependent upon the synthesis procedure.

The use of glassceramics in photocatalysis is an attractive option for the realization of smart optical fibers and self-cleaning windows. Here we present the photocatalytic activity of germanosilicate glasses embedding Ga2O3 nanocrystals prepared by batch melting and glass heat treatment. The powdered material is used for UV-assisted degradation of rhodamine in water. The kinetics show changes after repeated experiments. In the first cycle, the apparent rate is governed by a second-order reaction with a Gaussian-like shape, whereas the second cycle follows a first-order reaction. The modification appears to be correlated with perturbations in the defect population. Photoluminescence has been used to monitor the evolution of such defects. Kinetic data on photoreactions and defect formation have been modelled in a combined frame in which the defect concentration determines the photocatalytic activity. The results prove the photocatalytic ability of the studied glassceramics. Moreover, the general validity of the kinetic model can be of interest for other systems in which the photocatalytic response depends on photoreactive species concentration.

Among the materials for the negative electrodes in Li-ion batteries, oxides capable of reacting with Li+ via intercalation/conversion/alloying are extremely interesting due to their high specific capacities but suffer from poor mechanical stability. A new way to design nanocomposites based on the (Ti/Sn)O2 system is the partial oxidation of the tin-containing MAX phase of Ti3Al(1-x)SnxO2 composition. Exploiting this strategy, this work develops composite electrodes of (Ti/Sn)O2 and MAX phase capable of withstanding over 600 cycles in half cells with charge efficiencies higher than 99.5% and specific capacities comparable to those of graphite and higher than lithium titanate (Li4Ti5O12) or MXenes electrodes. These unprecedented electrochemical performances are also demonstrated at full cell level in the presence of a low cobalt content layered oxide and explained through an accurate chemical, morphological, and structural investigation which reveals the intimate contact between the MAX phase and the oxide particles. During the oxidation process, electroactive nanoparticles of TiO2 and Ti(1-y)SnyO2 nucleate on the surface of the unreacted MAX phase which therefore acts both as a conductive agent and as a buffer to preserve the mechanical integrity of the oxide during the lithiation and delithiation cycles.

Background: A structured approach involves systematic management of trauma patients. We aim to conduct an overview of reviews about the clinical efficacy and safety of structured approach (i.e., primary and secondary survey) by guideline checklist compared to non-structured approach (i.e. clinical examination); moreover, routine screening whole-body computer tomography (WBCT) was compared to non-routine WBCT in patients with suspected major trauma.Methods: We systematically searched MEDLINE (PubMed), EMBASE and Cochrane Database of Systematic Reviews up to 3 May 2022. Systematic reviews (SRs) that investigated the use of a structured approach compared to a non-structured approach were eligible. Two authors independently extracted data, managed the overlapping of primary studies belonging to the included SRs and calculated the corrected covered area (CCA). The certainty of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology.Results: We included nine SRs investigating two comparisons in stable trauma patients: structured approach vs non-structured approach (n = 1) and routine WBCT vs non-routine WBCT (n = 8). The overlap of included primary studies was generally high across outcomes (CCA ranged between 20.85 and 42.86%) with some discrepancies in the directions of effects across reviews. The application of a structured approach by checklist may improve adherence to guidelines (e.g. Advanced Trauma Life Support) during resuscitation and might lead to a reduction in mortality among severely injured patients as compared to clinical examination (Adjusted OR 0.51; 95% CI 0.30-0.89; p = 0.018; low certainty of evidence). The use of routine WBCT seems to offer little to no effects in reducing mortality and time spent in emergency room or department, whereas non-routine WBCT seems to offer little to no effects in reducing radiation dose, intensive care unit length of stay (LOS) and hospital LOS (low-to-moderate

Highly concentrated aqueous binary solutions of acetate salts are promising systems for different electrochemical applications, for example, energy storage devices. The very high solubility of CH3COOK allows us to obtain water-in-salt electrolyte concentrations, thus reducing ion activity and extending the cathodic stability of an aqueous electrolyte. At the same time, the presence of Li+ or Na+ makes these solutions compatible with intercalation materials for the development of rechargeable alkaline-ion batteries. Although there is a growing interest in these systems, a fundamental understanding of their physicochemical properties is still lacking. Here, we report and discuss the physicochemical and electrochemical properties of a series of solutions based on 20 mol kg-1 CH3COOK with different concentrations of CH3COONa. The most concentrated solution, 20 mol kg-1 CH3COOK + 7 mol kg-1 CH3COONa, gives the best compromise between transport properties and electrochemical stability, displaying a conductivity of 21.2 mS cm-1 at 25 °C and a stability window of up to 3 V in “ideal” conditions, i.e., using a small surface area and highly electrocatalytic electrode in a flooded cell. Careful Raman spectroscopy analyses help to address the interaction network, the phase evolution with temperature, and the crystallization kinetics.

Inorganic nanoparticles of boron-rich compounds represent an attractive alternative to boron-containing molecules, such as boronophenylalanine or boranes, for BNCT applications. This work describes the synthesis and biological activity of multifunctional boron carbide nanoparticles stabilized with polyacrylic acid (PAA) and a gadolinium (Gd)-rich solid phase. A fluorophore (DiI) was included in the PAA functionalization, allowing the confocal microscopy imaging of the nanoparticles. Analysis of the interaction and activity of these fluorescent Gd-containing B4C nanoparticles (FGdBNPs) with cultured cells was appraised using an innovative correlative microscopy approach combining intracellular neutron autoradiography, confocal, and SEM imaging. This new approach allows visualizing the cells, the FGdBNP, and the events deriving from the nuclear process in the same image. Quantification of 10B by neutron autoradiography in cells treated with FGdBNPs confirmed a significant accumulation of NPs with low levels of cellular toxicity. These results suggest that these NPs might represent a valuable tool for achieving a high boron concentration in tumoral cells.

Getting inspiration from the ‘waste to resource’ strategic theme of circular economy, herein, we present the upcycling of the critical raw material i.e. Co-containing waste cathode from spent lithium-ion batteries (LIBs) into platinum group metal-free (PGM-free) electrocatalysts for hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR). Lithium cobalt oxide-based cathode was recovered from spent LIBs (Waste LCOd) and subsequently treated with choline chloride: citric acid 1:1 deep eutectic solvent (DES) to obtain the full degradation of the LCO-type structure and, post thermal treatments, cobalt oxide in a carbonaceous matrix (ChCl.Citric). HER and ORR activities of derived materials were investigated in alkaline media using the rotating disk electrode (RDE) and rotating ring disk electrode (RRDE), respectively. To elucidate the role of cobalt present in the derived electrocatalysts, inks were prepared by supporting the electrocatalysts with different proportions of Ketjenblack (10:90 and 50:50 ratios). Waste LCOd closely followed the electrochemical response of commercial LCO and demonstrated the least overpotential (277 mV at −10 mA cm−2) for HER with an electrode configuration of 50:50. Whereas, ChCl.Citric 50:50 outperformed the other counterparts for ORR and exhibited a remarkable onset potential of 0.85 V (vs RHE) with the least peroxide production.