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Lithium nickel oxide (LNO) is an attractive positive electrode active material for lithium ion batteries (LIBs) due to its high reversible specific capacity and absence of cobalt. Nevertheless, it is prone to structural instabilities that lead to rapid capacity fading, safety concerns and shows in average a lower voltage than mixtures with cobalt, limiting its applicability to date. Herein this study introduces the sulfur‐based electrolyte additive, benzo[d][1,3,2]dioxathiole 2,2‐dioxide (DTDPh), to stabilize the LNO electrode and study its effects on interphase compositions by means of complementary electrochemical and spectroscopic techniques. Obtained results demonstrate an improved galvanostatic cycling performance in terms of cycle life and achievable specific discharge capacity that significantly outperform the common film‐forming additive vinylene carbonate (VC). The cycle life is increased from 102 to 147 cycles compared to the baseline electrolyte and the accumulated discharge energy until end of life is increased by 45%. This study furthermore provides strong evidence of a significant cross‐talk and negative interplay between DTDPh and VC when both are present in the electrolyte formulation. Mechanistic consideration based on density functional theory (DFT) calculations suggest the formation of mobile poly(VC) species, which is supported by the results of post mortem analysis of the resulting interphases. [ABSTRACT FROM AUTHOR]

We investigated the effects of X‐ray beam damage during X‐ray photoelectron spectroscopy measurement on LiNiO2 electrodes. The degree of damage induced by lab‐based and synchrotron X‐ray radiation has been compared between pristine and cycled electrodes, highlighting the role of positive solid electrode–electrolyte interphase to protect the cycled LiNiO2 surface from beam damage. The possible steps to avoid or at least reduce the beam‐induced effects are outlined. [ABSTRACT FROM AUTHOR]

Addressing the oxidation state of functional materials such as transition metal oxides is a current critical challenge and requires new methodologies to characterize their electronic structure within surface to bulk resolution at the nanometer scale. One approach to this issue is the combination of co‐localized soft and hard X‐ray photoelectron spectroscopies for a non‐destructive depth profiling. In this work, we demonstrate the capability to characterize the oxidation state of cobalt in LiCoO2 thin films, a model electrode material in the Li‐ion battery field, within the first 15 nm. The capability of the methodology to address the surface evolution of the cobalt oxidation state is tested through a proof of concept surface modification introduced by Ar‐ion sputtering. To address the cobalt local electronic structure at different depths from the extreme surface, we exploited Auger‐free Hard X‐ray photoelectron spectroscopy (HAXPES) spectra to fit the Co 2p core‐level features in the X‐ray photoelectron spectroscopy (XPS) spectra. This approach may pave the way for a better understanding of the surface electronic structure changes in transition metal oxides driven by their applications in a broad range of technologies. [ABSTRACT FROM AUTHOR]

Using Si as anode materials for Li-ion batteries remain challenging due to its morphological evolution and SEI modification upon cycling. The present work aims at developing a composite consisting of carbon-coated Si nanoparticles (Si@C NPs) intimately embedded in a three-dimensional (3D) graphene hydrogel (GHG) architecture to stabilize Si inside LiB electrodes. Instead of simply mixing both components, the novelty of the synthesis procedure lies in the in situ hydrothermal process, which was shown to successfully yield graphene oxide reduction, 3D graphene assembly production, and homogeneous distribution of Si@C NPs in the GHG matrix. Electrochemical characterizations in half-cells, on electrodes not containing additional conductive additive, revealed the importance of the protective C shell to achieve high specific capacity (up to 2200 mAh.g−1), along with good stability (200 cycles with an average Ceff > 99%). These performances are far superior to that of electrodes made with non-C-coated Si NPs or prepared by mixing both components. These observations highlight the synergetic effects of C shell on Si NPs, and of the single-step in situ preparation that enables the yield of a Si@C-GHG hybrid composite with physicochemical, structural, and morphological properties promoting sample conductivity and Li-ion diffusion pathways. [ABSTRACT FROM AUTHOR]

Lithium metal electrodes have been submitted to a long-term storage in contact with carbonated-based electrolyte at different temperatures, with the aim of gaining more understanding on the impact of aging conditions on the lithium metal surface. To do so, the evolution of lithium surface∣electrolyte interface has been monitored via electrochemical impedance spectroscopy, X-ray photoelectron spectroscopy and FE-SEM techniques, to correlate the change of the interface properties with the chemical and morphological modifications at the electrode’s surface. After this aging, lithium electrodes were galvanostatically cycled in symmetric Li∣Li coin cell configuration at 10, 25 and 45 °C. Through this approach, a better cycling stability was observed in those cells stored at 45 °C, which can be ascribed to the more compact lithium electrodeposition than that observed in the rest of cells previously aged at lower temperatures. These results indicate that calendar at high temperature condition benefits lithium electrode performance, which can be attributed to a homogeneous passivation of the metal surface with fluorine and/or phosphate-based compounds, following XPS measurements, which can improve the behaviour of the solid electrolyte interface. [ABSTRACT FROM AUTHOR]

The timely arrival of novel materials plays a key role in bringing advances to society, as the pace at which major technological breakthroughs take place is usually dictated by the discovery rate at which novel materials are identified within chemical space. High‐throughput experimentation and computation strategy, now widely considered as a watershed in accelerating the discovery and optimization of novel materials in virtually every field, enables simultaneous screening, synthesis and characterization of large arrays of different material classes toward identification of the lead candidates for given system and targeted application. However, the ability to acquire data, through the continued advancement of automation platforms and workflows especially in the field of battery research and development, often outpaces the ability to optimally leverage obtained data for improved decision‐making. Closing this gap inevitably calls for adapted algorithms, development of reliable predictive models and enhanced integration with machine learning, deep learning, and artificial intelligence. This Review aims to highlight state‐of‐the‐art achievements along with an assessment of current and future challenges as well as resulting perspectives toward accelerated development of advanced battery electrolytes and their interfaces. [ABSTRACT FROM AUTHOR]

Driven by the continuous search for improving performances, understanding the phenomena at the electrode/electrolyte interfaces has become an overriding factor for the success of sustainable and efficient battery technologies for mobile and stationary applications. Toward this goal, rapid advances have been made regarding simulations/modeling techniques and characterization approaches, including high‐throughput electrochemical measurements coupled with spectroscopies. Focusing on Li‐ion batteries, current developments are analyzed in the field as well as future challenges in order to gain a full description of interfacial processes across multiple length/timescales; from charge transfer to migration/diffusion properties and interphases formation, up to and including their stability over the entire battery lifetime. For such complex and interrelated phenomena, developing a unified workflow intimately combining the ensemble of these techniques will be critical to unlocking their full investigative potential. For this paradigm shift in battery design to become reality, it necessitates the implementation of research standards and protocols, underlining the importance of a concerted approach across the community. With this in mind, major collaborative initiatives gathering complementary strengths and skills will be fundamental if societal and environmental imperatives in this domain are to be met. [ABSTRACT FROM AUTHOR]

Lithium-rich disordered rocksalt Li2TiS3 offers large discharge capacities (>350 mAh·g−1) and can be considered a promising cathode material for high-energy lithium-ion battery applications. However, the quick fading of the specific capacity results in a poor cycle life of the system, especially when liquid electrolyte-based batteries are used. Our efforts to solve the cycling stability problem resulted in the discovery of new high-energy selenium-substituted materials (Li2TiSexS3−x), which were prepared using a wet mechanochemistry process. X-ray diffraction analysis confirmed that all compositions were obtained in cation-disordered rocksalt phase and that the lattice parameters were expanded by selenium substitution. Substituted materials delivered large reversible capacities, with smaller average potentials, and their cycling stability was superior compared to Li2TiS3 upon cycling at a rate of C/10 between 3.0–1.6 V vs. Li+/Li. [ABSTRACT FROM AUTHOR]

Carbon black (CB) filled elastomers are structurally complex materials that offer unique properties at different length scales. They have tremendous potential applications in a number of fields including the automotive and aerospace industries and for designing innovative smart materials such as artificial muscles but their applications remain limited primarily due to inadequate understanding of their unique mechanical properties. Here, using the Berkovich technique to probe the surface mechanical properties at different scales the nanoindentation response of a series of composites made by homogeneously dispersed CB nanoparticles inside a semicrystalline copolymer matrix has been explored. While the measured loading part of the force–displacement curves is well described by Meyer's empirical power relation, the inverted methodology (IM) approach to deal with the unloading part has been considered and its outcome has been compared with that obtained from the standard Oliver–Pharr's method. The results were consistent with the observed increase of hardness when the applied displacement decreases for all composite samples over a large range of CB volume fraction. Zhang and Xu's model is demonstrated to produce experimentally consistent explanation of this indentation size effect. X‐ray photoelectron spectroscopy (XPS) spectra also show composition gradients with depth up to 100 nm. Furthermore, the effect of CB content, surface features, and length scale‐dependent deformation on the hardness–displacement behavior have been considered. These findings highlight the possibility of attaining a diverse set of mechanical properties by a better understanding of the nanoindentation response of CB filled elastomers which can be useful for material selection and design improvements in a number of practical applications. [ABSTRACT FROM AUTHOR]

Controlling the stoichiometry of supported bimetallic nanoparticles is essential in many catalytic reactions, notably selective CO 2 hydrogenation. Thus, a new strategy to ensure the preferred stoichiometry (1:1) of supported bimetallic PdZn nanoparticles is presented, involving the deposition of a heterobimetallic precursor, [PdZn(μ-OOCMe) 4 ] 2 on a CeZrO x support. After calcination and reduction, the material contained mainly a PdZn alloy, as revealed by powder XRD and XAFS, and further supported by XPS, TEM-EDX, elemental analysis and in-situ IR at low temperature using CO as probe molecule. Moreover, a minor phase of oxidized Zn was determined by XAFS. This PdZn/CeZrOx reduced catalyst was combined with SAPO-34 to form a tandem catalytic system for CO 2 conversion to hydrocarbons. This system could readily convert CO 2 and H 2 at high temperature (380 °C) into hydrocarbons with a conversion of 24% and high relative selectivity in light hydrocarbons (C2–C3: 82%) with virtually no deactivation of the catalyst after 16 h on stream. Controlled experiments were performed with Pd/CeZrOx and Zn/CeZrOx in order to gain supplementary insights on this system: Pd/CeZrOx gave only methane and Zn/CeZrOx gave mainly CO under the same conditions. The latter clearly shows that the control of the formation of PdZn phase has great impact for the selective production of hydrocarbons. [Display omitted] • Development of PdZn supported on CeO 2 , ZrO 2 and CeZrOx for the conversion of CO 2 to methanol. • Catalyst PdZn/CeZrOx presents highly dispersed bimetallic PdZn nanoparticles with 1:1 ratio. • CO 2 conversion to light hydrocarbons is studied over tandem catalysts comprising PdZn supported on oxide and SAPO-34. • PdZn/CeZrOx/SAPO-34 catalysts present high CO 2 conversion and selectivity in light hydrocabons. [ABSTRACT FROM AUTHOR]

Lithium-rich disordered rocksalt Li2TiS3 offers large discharge capacities (>350 mAh·g−1) and can be considered a promising cathode material for high-energy lithium-ion battery applications. However, the quick fading of the specific capacity results in a poor cycle life of the system, especially when liquid electrolyte-based batteries are used. Our efforts to solve the cycling stability problem resulted in the discovery of new high-energy selenium-substituted materials (Li2TiSexS3−x), which were prepared using a wet mechanochemistry process. X-ray diffraction analysis confirmed that all compositions were obtained in cation-disordered rocksalt phase and that the lattice parameters were expanded by selenium substitution. Substituted materials delivered large reversible capacities, with smaller average potentials, and their cycling stability was superior compared to Li2TiS3 upon cycling at a rate of C/10 between 3.0−1.6 V vs. Li+/Li.