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To improve the electrochemical performance of the LiNi 0.5 Mn 1.5 O 4 high voltage cathode for Lithium Ion Batteries, silicon-doped LiNi 0.5 Mn 1.5−x Si x O 4 samples (0.00 ≤ x ≤ 0.35) were prepared by different synthesis routes (solid-state reaction and ball milling) and characterized. The X-ray diffraction investigation and structural and profile Rietveld refinement put into evidence that effective spinel doping is obtained by the ball milling route: a solubility limit is achieved for x = 0.10 and silicon preferentially occupies the 8a tetrahedral site of the spinel structure, thus causing lithium to occupy both the tetrahedral and octahedral sites. In contrast, segregation of lithium silicates in the solid-state synthesis is observed. SEM images show that, independent on the synthesis method, silicon controls the particles morphology and grain size. The doped samples show improved electrochemical performances, which can be ascribed to the role of silicon in increasing cations disorder and controlling particles size.

Rechargeable all solid-state lithium batteries are a promising technology for the next generation of safer batteries. In this context, strict requirements are placed on the electrolytes, among which is emerging the Li7La3Zr2O12 garnet, chiefly for the relationships among synthesis conditions and phase stability. Here, the structural modifications of the low temperature (LT) Li7La3Zr2O12 cubic form were investigated by using in situ X-Rays diffraction analysis. In particular, we studied the role of both temperature and atmosphere (air or argon) on phase stabilization. In argon flow, the LT phase is stable under 750 °C, and it transforms into the tetragonal one at lower temperature. In air, it partially decomposes to La2Zr2O7 due to Li loss above 250 °C. ICP-OES analysis confirmed that garnet stoichiometry was maintained in argon, whereas in air lithium loss occurred. The structural transformations are driven by the CO2 absorbed in the LT structure that can form Li2CO3 and/or La2(CO3)3 so causing stoichiometry changes responsible of the structural evolution.

In this study, the maple wood surface was coated with nanostructured zinc oxide, grown on the surface by using a hydrothermal process, and furtherly treated with shellac varnish. Samples obtained both after ZnO treatment and after the final varnish application were characterized by different techniques, i.e., X-ray diffraction (XRD), scanning electron microscopy combined with energy-dispersive X-ray spectroscopy (SEM-EDS), micro-FTIR with attenuated total reflectance (μ-ATR-FTIR), chromatic variation measurements, and contact angle determinations. Analytical results showed that the wood surface was covered by quite a homogeneous array of inorganic nanoparticles and that the natural resin forms a regular film over the ZnO nanostructures. An accelerated aging test was used to evaluate the protecting effectiveness of the treatments towards UV-induced decay of wood material. After the test, wood treated with ZnO and with the shellac/ZnO combination underwent a considerably lower chromatic change if compared to the untreated wood, suggesting an enhanced resistance of the treated maple to the decay due to light exposition. The presence of nanostructured ZnO protects from decay not only the wood substrate but also the shellac film. A microbiology test showed that growth of fungal species, e.g., common mold, is prevented on the wood surface treated with ZnO or with shellac/ZnO, indicating that the nanostructured zinc oxide also provides an effective protection from biodeterioration. The coating obtained by consecutive application of nanosized ZnO particles and shellac varnish combines the excellent aesthetical features and water repellence of the traditional finish with the protecting effectiveness of the nanostructured inorganic component.

Two different zinc-based metal-organic frameworks (MOFs) were investigated to remove one of the most used fluoroquinolone antibiotic, Ofloxacin (OFL), from polluted water. The most common zeolitic imidazolate framework-8 (ZIF-8) and the green Zn(II) and benzene-1,3,5-tri-carboxylate (Zn3(BTC)2) were prepared through a facile synthetic route and characterized by means of Fourier-Transform Infrared (FT-IR) Spectroscopy, X-Ray Powder Diffraction (XRPD), and Scanning Electron Microscopy (SEM) analyses. The two MOFs were compared in terms of both adsorption and kinetic aspects under real conditions (tap water, natural pH). Results showed that OFL was adsorbed in remarkable amounts, 95 ± 10 and 25.3 ± 0.8 mg g−1 on ZIF-8 and Zn3(BTC)2, respectively, following different mechanisms. Specifically, a Langmuir model well described the ZIF-8 profile, while for Zn3(BTC)2, cooperative adsorption occurred. Moreover the kinetic results were quite different, pseudo-second-order and sigmoidal, respectively. The suitability of ZIF-8 and Zn3(BTC)2 as adsorbent phases for water depollution was tested on tap water samples spiked with OFL 10 µg L−1. The obtained removal efficiencies, of 88% for ZIF-8 and 72% for Zn3(BTC)2, make these materials promising candidates for removing fluoroquinolone antibiotics (FQs) from polluted waters, notwithstanding their limited reusability in tap water, as demonstrated by in-depth characterization of the two MOFs after usage.

Phosphorus is an essential nutrient for plants, which use it as a basic fertilizer component and is expected to increase significantly in the coming years due to higher food crops demand. Unfortunately, the available phosphorus natural reserves are not renewable, and estimates indicate their rapid decline in the future. Urban wastewater, due to its abundance and relatively high phosphorus content, is an excellent candidate for phosphorus recovery, while the element&rsquo, s removal from urban effluents was introduced in the 1970&prime, s to limit the undesired effects of eutrophication. In this study, the process of struvite (and related phosphorous compounds) crystallization was investigated for three different sludge types, and the results were compared. While most studies focus strictly on anaerobically digested sludge for high struvite precipitation efficiency, this study investigated the possibility of inducing precipitation on both aerobic (extended aeration) and anaerobic sludges produced by two wastewater treatment plants in northern Italy. Analysis of precipitates from sludge samples was compared, where the focus was on the aerobic sludge, and its potential for struvite recovery. The effect of different reaction parameters was studied under different operating conditions, and the use and effects of Ca(OH)2 addition as an inexpensive potential pH adjustment reagent was investigated.

Improving cathode materials is mandatory for next-generation Li-ion batteries. Exploring polyanion compounds with high theoretical capacity such as the lithium metal orthosilicates, Li2MSiO4 is of great importance. In particular, mixed silicates represent an advancement with practical applications. Here we present results on a rapid solid state synthesis of mixed Li2(FeMnCo)SiO4 samples in a wide compositional range. The solid solution in the P21/n space group was found to be stable for high iron concentration or for a cobalt content up to about 0.3 atom per formula unit. Other compositions led to a mixture of polymorphs, namely Pmn21 and Pbn21. All the samples contained a variable amount of Fe3+ ions that was quantified by Mössbauer spectroscopy and confirmed by the TN values of the paramagnetic to antiferromagnetic transition. Preliminary characterization by cyclic voltammetry revealed the effect of Fe3+ on the electrochemical response. Further work is required to determine the impact of these electrode materials on lithium batteries.

Olivine-type LiFePO4 is nowadays one of the most important cathode materials of choice for highenergy lithium ion batteries. Its intrinsic defectivity, and chiefly the so-called lithium iron anti-site, is one of the most critical issues when envisaging electrochemical applications. This paper reports a combined diffractometric (Synchrotron Radiation XRD with Rietveld and PDF analyses) and spectroscopic (Moessbauer) approach able to give a thorough characterization of the material defectivity. Such analytical procedure has been applied to a sample prepared following an innovative microwave-assisted hydrothermal synthesis route that, in a few minutes, allowed us to obtain a well crystallized material. PDF analysis, which is applied for the first time to this type of battery material, reveals the presence of disorder possibly due to Li/Fe exchange or to a local symmetry lowering. A 5% amount of iron on the lithium site has been detected both by PDF as well as by Moessbauer spectroscopy, which revealed a small percentage of Fe3+ on the regular sites.

The role of lithium excess and Mn doping on lithium titanium phosphate properties is studied by structural (X-ray and neutron diffraction) and spectroscopic (electron paramagnetic resonance and impedance) techniques. The dopant cation is present with 2+, 3+, and 4+ oxidation states in both the lithium and titanium sublattices: Mn2+ is preferentially located on Li sites and Mn4+ on Ti ones, and Mn3+ can occupy both the sites. The refinement of neutron diffraction patterns allowed us to identify the 18e crystallographic site as the preferred location of the excess Li ions. Cationic distribution and valence state are mainly related to sol–gel or solid-state synthesis routes. Consequently, the complex behavior of the bulk conductivity can be explained by the presence of Mn on the Li site and the amount of Li excess, while the effect of the sintering degree is comparable in all the samples as revealed by scanning electron microscopy.

Structural, microstructural, and spectroscopic properties of Ba6Zr2Ta8O30 (BZT) and Ba6Zr1.94M0.06Ta8O30 (M = Ni, Co, Fe, Mn, Cr) related doped compounds are reported. The distribution of Zr, Ta, and M dopant ions on the cationic sites and the M valence states are discussed on the basis of the results obtained by the application of the Rietveld method on X-ray powder diffraction (XRPD) patterns and by electron paramagnetic resonance. The micro-Raman spectra of pure and doped BZT, reported and discussed for the first time, confirm the capability of the lattice to host transition cations in a glasslike matrix. The particle size effects of the samples are investigated by analyzing XRPD line broadening and scanning electron microscopy observations. Comparisons with the isostructural pure and doped Ba6Ti2Nb8O30 compounds are also reported.

Lithium-ion batteries are by far the most important storage devices available on the market. At present, they dominate the sector of portable electronics and are the solution of choice in the automotive sector. Other important applications are also foreseen, including storage in electric grids. However, these future markets do require energy density higher than lithium-ion batteries could reasonably deliver in the near future. To this end, other lithium-based chemistries are currently under study, including lithium–air (oxygen) and lithium–sulfur. In this chapter, we will briefly discuss the state-of-the-art and the major scientific and technological challenges underlying the development of lithium-ion and, chiefly, post lithium-ion batteries.

Li-air batteries are considered one of the future systems of choice for massive energy storage in automotive and smart grids. In this chapter, we will describe the cell designs developed up to now, with emphasis on aqueous and nonaqueous aprotic electrolyte architectures. Then, we will focus the attention on the cathode compartment, and the carbon-based nanomaterials (including nanotubes and graphene) employed will be critically discussed.

The charge distribution in the Mg-doped lithium manganese spinel Li 1.02 Mg x Mn 1.98− x O 4 with 0.00 x ≤0.20 is discussed and compared to those pertinent to other M-doped samples (M=Ni 2+ , Co 3+ , Cr 3+ , Al 3+ and Ga 3+ ). EPR spectra, low temperature X-ray diffraction and conductivity data are related to the cooperative Jahn–Teller (J–T) transition occurring at about 280 K in the undoped sample. The sensitivity of the cationic sublattice in displaying electronic and magnetic changes after substitution is remarked. The inhibition of the J–T transition is related to the ratio r =|Mn 4+ |/|Mn 3+ | as deduced from the charge distribution model [Li 1− x t + Mg x t 2+ ] tetr [Li y + x t + Mg x o 2+ Mn 1−3 y −2 x 3+ Mn 1+2 y + x 4+ ] octa where x = x o + x t . For y =0.02 and x =0.02, a value r =1.177 is obtained, very close to r lim =1.18, the limit value beyond which the transition is inhibited.

In this work we reported, for the first time, the preparation by radio frequency sputtering and the electrochemical characterization of Li/M/Si/O thin films (M = Fe, Mn), as positive electrodes for lithium microbatteries. The deposited films were amorphous both in case of pure iron and mixed iron/manganese compositions. The electrochemical performances, in terms of capacity values and coulombic efficiency, were comparable to those currently reported for the corresponding crystalline bulk materials. In particular, capacities of the order of 50 mAh g −1 were obtained at 2.5 C with coulombic efficiency near 90% by using a standard liquid electrolyte. Our preliminary electrochemical results, together with the easiness of preparation, suggested that Li/M/Si/O thin films could be interesting candidates as cathodes in lithium microbatteries.

Electron paramagnetic resonance (EPR) and static magnetization data on manganese substituted (up to 3 mol%) strontium tintanate (Mn:SrTiO3) samples are presented. Four EPR signals are observed from different Mn4+ and Mn2+ sites. The behavior of their intensity vs. temperature is discussed. It suggests the presence of antiferromagnetic interactions in heavily Mn doped grain boundaries. X-ray diffraction analysis shows two coexisting perovskite-type phases, whose abundance depends on the Mn content. (C) 2000 Elsevier Science Ltd. All rights reserved.

The electrical conductivity of lithium-manganese spinels is analyzed in samples with different starting Li cationic fraction x. Li-rich spinels, resulting from Li-Mn substitution around the stoi-chiometric value (x= 0.333), show conductivity values higher than that observed in stoichiometric LiMn2O4 . Besides, a conductivity drop, associated with a structural phase transition at about 290 K in LiMn2O4 , progressively disappears by decreasing x, while it is absent in Li-rich samples. Stoi-chiometry effects on the concentration of charge carriers and on the available sites for the hopping transport process are evaluated, as well as the effects due to coexisting insulating phases. The role of the Jahn-Teller effect on the conductivity behaviour of stoichiometric and Li-poor spinels is also considered.

X-ray diffraction (XRD) and $^{7}\mathrm{MAS}$ measurements have been performed on ${\mathrm{LiMn}}_{2}$${\mathrm{O}}_{4}$ (lithium cationic fraction, x=0.333), ${\mathrm{Li}}_{2}$${\mathrm{MnO}}_{3}$ (x=0.667), and the intermediate composition with x=0.40. The use of magic angle spinning produces complex manifolds of the spinning sidebands. The predominant interaction affecting the NMR spectrum is the transferred hyperfine coupling (TFHI) between the Mn ions and the Li spins. TFHI parameters are extracted from MAS-NMR spectra of oxides containing a large quantity of manganese. We obtained a full spectral assignment for the spinel ${\mathrm{LiMn}}_{2}$${\mathrm{O}}_{4}$, for the rocksalt ${\mathrm{Li}}_{2}$${\mathrm{MnO}}_{3}$, and for the x=0.40 sample, which contains the rocksalt and both stoichiometric and nonstoichiometric spinel phases. According to XRD data, the rocksalt phase contains three nonequivalent lithium sites whose NMR peaks are shifted upfield from x=0.667 to 0.40 because of the cell volume expansion.mThe ${\mathrm{Li}}^{+}$ ions belonging to the two spinel phases of x=0.40 are quite mobile and give origin by motional narrowing to a single peak, which is slightly shifted upfield with respect to that of ${\mathrm{LiMn}}_{2}$${\mathrm{O}}_{4}$.

The coexistence of LiMn 2 O 4 and Li 2 MnO 3 phases from MnO/Li 2 CO 3 mixtures with lithium cationic fraction 0.33≤ x ≤0.53 was studied by X-ray diffraction (XRD) and electron paramagnetic resonance (EPR) measurements. XRD quantitative phase analysis was carried out using the Rietveld profile refinement procedure, while the Li 2 MnO 3 percentage was determined directly by comparing the EPR intensities with the intensity of the pure Li 2 MnO 3 spectrum. The experimental results show the presence of an Li-rich spinel phase and allow an estimation of the lithium excess, since the structural analysis of pure Li 2 MnO 3 samples evidenced a nearly stoichiometric composition ( x =0.663) with very limited cationic disorder.

International audience; Transition metal-based lithium orthosilicates (Li2MSiO4, M=Fe, Ni, Co, Mn) are gaining a wide interest as cathode materials for lithium-ion batteries. These materials present a very complex polymorphism that could affect their physical properties. In this work, we synthesized the Li2FeSiO4 and Li2MnSiO4 compounds by a sol-gel method at different temperatures. The samples were investigated by XRPD, TEM, Li-7 MAS NMR, and magnetization measurements, in order to characterize the relationships between crystal structure and magnetic properties. High-quality Li-7 MAS NMR spectra were used to determine the silicate structure, which can otherwise be hard to study due to possible mixtures of different polymorphs. The magnetization study revealed that the Neel temperature does not depend on the polymorph structure for both iron and manganese lithium orthosilicates.

X-ray diffraction, magnetic susceptibility, and electron paramagnetic resonance (EPR) measurements have been carried out on mixed nickel-lithium oxides as a function of the lithium content. The experimental results allow us to analyze the cationic order and the magnetic interactions. All the data are consistent with a model that admits coexistence of different structural phases in a wide composition range, previously not accounted for in the discussion of the physical properties of these mixed oxides. \textcopyright{} 1996 The American Physical Society.

Co and Li{sub 2}CO{sub 3} were used as starting materials to obtain cobalt-based plaques of potential use in molten carbonate fuel cell technology. Samples were prepared by thermal treatments in the temperature range 800-1300{degrees}C. Their composition and microstructure have been investigated at room temperature by X-ray diffraction analysis (Rietveld refinement), weight change and density data, porosimetry, and scanning electron microscopy. It is shown that a highly nonstoichiometric Co{sub 3}O{sub 4} forms on lithium-containing samples in the entire temperature range investigated, while a stoichiometric Co{sub 3}O{sub 4} is always obtained in the absence of Li. Moreover, clear evidence has been obtained that sinterization starts at lower temperatures on lithiated samples than on pure Co ones and that it causes the formation of consistent amounts of stoichiometric CoO in both types of sample. It is argued that the increased sinterization rate shown by Li-containing samples is due to the highly defective structure of their Co{sub 3}O{sub 4} phase.

DSC measurements in the 25–240°C temperature range have been performed on sulphur—selenium physical mixtures (1.99–95.06 mass% of Se) in order to clarify the interaction mechanism. The experimental results can be interpreted on the basis of an interaction model according to which a S/Se copolymerization process takes place in mixtures with Se contents up to 55 mass%. Beyond the 55 mass% Se content the interaction mechanism appears to shift towards an “anomalous melting” behaviour of the two components.

The optical properties of sol–gel prepared Cerium doped Lutetium and Yttrium oxyorthosilicates are investigated in the vacuum ultraviolet energy range by means of synchrotron radiation. The excitation and emission properties are compared to commercial samples grown by Czochralski method. The sol gel polycrystals do show emission features comparable to the ones of the monocrystals but with a slightly smaller decay time. Preliminary radioluminescence measurements indicate the possibility to apply the sol gel synthesized polycrystals as scintillating materials in the low X-ray energy range.

We investigate the influence of particle size and crystal orientation on the electrochemical behavior of carbon-coated LiFePO4 prepared by a hydrothermal synthesis in the presence of a polymeric surfactant and a source of carbon. We evaluated the charge/discharge profiles of two samples, one constituted by particles in the micrometer range with a platelet-like shape (large ac facet and (020) crystal orientation) and another made of sub-micrometer-rounded particles with a random crystal orientation. At low current rates the crystal orientation seems to be the prevailing factor, whereas at high current rates smaller particles can allow a shorter electronic conduction path, so reducing the resistance experienced by Li ions during diffusion.

Gravimetric, dilatometric, diffractometric and microscopic measurements have been used to study the role of thermal treatment in the preparation of lithiated nickel oxide cathodes for molten carbonate fuel cells. Clear evidence has been obtained that both the nominal composition of the reactive system and the thermal treatment during solid solution formation appreciably affect the cathodes microstructure. Starting from a careful analysis of the X-ray data, a reaction model is proposed which quite satisfactorily explains the microstructural aspects of the reaction. It is shown that there are three different processes at the origin of the cathodes microstructure and that the effect of the thermal treatment is to affect their relative weights.

Bioactive glasses and glass-ceramics of the system SiO2-P2O5-CaO with and without zinc were synthesized by sol-gel with the aim to address the influence of both the chemical composition and the microstructure on the growth of hydroxycarbonate apatite (HCA) following soaking in simulated body fluid (SBF). In the standard compositions 58S, 70S, and 80S the silica precursor was also partially replaced with a nanoscale silica powder (HiSil) in order to separate the contributions of porosity and composition. The combined use of XRPD, N2 absorption measurements, and SEM allowed us to establish quantitative correlations among the above-mentioned quantities. We found that the HCA formation rate increases with the silica content and that an important role is played by the specific surface area of the samples. Notably, the addition of even small quantities (0.4 wt%) of ZnO at the expenses of both CaO and P2O5 in the 58S glass leads to the increase, with respect to the 58S sample, of both the HCA formation rate and the HCA content after 8 days of treatment in SBF. A preliminary result revealed that sample with 0.4 wt % ZnO displayed good in vitro biocompatibility as shown by LDH assay

A DSC characterization of the sulfur-tetracyanoethylene (TCE) system was performed, and the thermal traces obtained quantitatively analyzed. It was shown that (a) some type of solid state interaction takes place between sulfur and TCE, which forces part of the sulfur to be “frozen” into its rhombic form; (b) variable amounts of sulfur and TCE fail to melt at their expected melting temperatures; and (c) a much higher than expected enthalpy change is associated with sulfur polymerization. A phenomenological model is proposed according to which the sulfur and TCE that fail to melt at their melting temperatures undergo fusion in the wake of the liquid-phase sulfur polymerization process. It is shown that the model proposed is valid in the entire composition range studied.

Clear evidence was obtained by dilatation and density measurements that the amount of lithium carbonate in the starting mixture sensibly affects the sintering behaviour of mixed lithium-nickel oxide cathodes. Porosimetric, diffractometric and microscopic measurements were then performed to understand and put on a quantitative basis such an influence. It is shown that, when the sintering temperature is low enough to prevent lithium oxide loss from the mixed oxide, cathodes total porosity increases with increasing lithium content up to a limiting composition beyond which a porosity decrease takes place. Lithium oxide loss, on the other hand, leads to a total porosity decrease which is related both to the initial lithium content and to the amount of the lithium oxide lost. Such a behaviour can be explained on the basis of the different mechanism by which the mixed oxide is obtained depending on the relative amounts of nickel and lithium carbonate in the starting mixture. Moreover it is shown that the observed total porosity changes are mainly a consequence of microporosity changes.

The room temperature cation occupancy in LiMgVO(4) and LiZnVO(4) crystallographic sites is obtained by means of the combined use of X-ray powder diffraction (XRPD), (7)Li and (51)V magic angle spinning nuclear magnetic resonance (MAS NMR), and micro-Raman measurements. In the LiMgVO(4) Cmcm orthorhombic structure, the 4c (C(2)(v) symmetry) tetrahedral vanadium site is fully ordered; on the contrary, the Li 4c tetrahedral site and the 4b (C(2)(h) symmetry) Mg octahedral site display about 22% of reciprocal cationic exchange. Higher cationic disorder is observed in LiZnVO(4): the three cations can distribute on the three tetrahedral and distinct sites of the R-3 structure. XRPD and MAS NMR analysis results highly agree for what concerns vanadium ion distribution on the three cationic sites (about 25, 26, and 47%). From the full profile fitting of XRPD patterns with the Rietveld method, it is also obtained that Li(+) displays a slightly preferred occupation of the T1 position (approximately 55%) and Zn(2+) of the T2 position (approximately 46%). The vibrational spectra of the two compounds are characterized by different peak positions and broadening of the Raman modes, reflecting the cation distribution and the local vibrational unit distortion. A comparison is also made with recent Raman results on Li(3)VO(4). High temperature XRPD measurements rule out possible structural transitions up to 673 K for both compounds.

Lithium manganese spinel Li1+yMn2-yO4 (0.0 less than or equal to y less than or equal to 0.07) synthesized by the sol-gel process is studied with a focus on the effects of the changes of formation conditions which can sensibly determine the mean crystallite size from a few nanometers to several hundred nanometers. Changes of stoichiometry and abundance of the spinel phase can be observed in the 573 less than or equal to T-A (K) less than or equal to 1073 range of annealing temperature (T-A). Comparing spinel phases obtained by sol-gel and solid state synthesis evidences the correlation among composition, structure, and electric and magnetic properties. (C) 1999 Academic Press.

Magnetic susceptibility measurements and electron paramagnetic resonance spectra of samples prepared from the reactive system MnO/Li2CO3 with different starting Li cationic fraction x are analyzed, taking into account the structural and compositional information provided by x-ray diffraction. Parent phases, as Mn2O3 , Mn3O4 and Li2 MnO3 , arise together with the lithium-manganese spinel as a result of Li-deficiency or Li-excess with respect to the x = 0.33 composition pertinent to the stoichiometric LiMn2O4 spinel. The data show that the spinel phase can sustain a partial Li-Mn substitution in the cation sites, according to compositional models described, for x > 0.33, by Li1+y Mn3+ 1-3y Mn4+ 1+2y O4 (Li-rich spinel) and, for x< 0.33, by Li1-|y| Mn2+ |y| Mn3+ 1+|y| Mn4+ 1-|y| O4 (Li-poor spinel). Paramagnetic resonance data of the Li-poor spinel phase are analyzed to discuss the possible oxidation state of Mn in the tetrahedral site.

Li2MSiO4 (M = Fe, Mn, etc.) are promising cathode materials for Li-ion batteries. One appealing strategy for improving their cathode properties is to develop mixed transition metal compounds. Density Functional Theory calculations were performed to evaluate the structural, magnetic and electrochemical properties of Li2M0.5N0.5SiO4 compounds. Our theoretical study allows us to individuate the most promising candidates for practical applications in lithium batteries.

Corrigendum to “Optical properties of sol gel prepared Cerium doped Lutetium and Yttrium oxyorthosilicates” [Journal of Non–Crystalline Solids 357 (8–9) (2011 April 15) 1908–1911] P.C. Ricci , C.M. Carbonaro⁎, L. Stagi , A. Anedda, F. Ferrari , D. Capsoni , A. Magistris c a Dipartimento di Fisica, Universita di Cagliari, s.p. n 8 Km 0.700, 09042 Monserrato, Cagliari, Italy b Centro Grandi Strumenti Universita di Cagliari, s.p. n 8 Km 0.700, 09042 Monserrato, Cagliari, Italy c Dipartimento di Fisica Chimica, Universita di Pavia, V.leTaramelli 16, I-27100 Pavia, Italy