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A sustainable process is designed to produce anode‐supported solid oxide fuel cells (SOFCs). Environmentally friendly solvents and additives are selected to prepare sequentially cast slurries to obtain a flexible multilayer tape whose cohesion is ensured by a 3D network of binder. This tape includes the components of the oxide precursor of the half cell with the functional and structural part of the anode. The optimization of debinding and sintering processes allows converting green tape into sintered multilayer ceramic using a single heat treatment. The use of optimized loads maintains planarity of samples with adjusted shape (circular to square) and size (from 0.8 up to 8 cm2) of anodic half cell. The cell's oxide precursor is supplemented by screen printing the cathode and converted to anode‐support SOFC when the cell is first used. The whole process maintains mechanical integrity, microstructure of structured components, and insures interfaces enabling charge transfer high enough to achieve standard performances such as power of 411 mW cm−2. The selection of cheap and harmless solvents and additives and the optimization of heat treatment lead to an ecocompatible low‐cost process for manufacturing SOFCs, easily transferable to the industrial scale and suitable for the manufacture of all systems based on ceramic multilayers. [ABSTRACT FROM AUTHOR]

A low‐cost manufacturing procedure has been developed for the fabrication of planar anode‐supported solid oxide fuel cell including only two thermal treatments. This method is also environmental friendly because slurries are water based and use nontoxic additives. Slurries are formulated by optimizing the powder quantity, by minimizing the organic compounds while controlling their stabilities and their rheological properties. Flexible multilayer green tapes have been produced by using the reverse sequential tape‐casting method. After a cosintering thermal treatment under loads, planar anodic half‐cells have been produced allowing the deposition of a La2NiO4+δ cathode by screen printing. After the final consolidation thermal treatment, the cell presents a 30 μm‐thick porous cathode, a 530 μm‐thick NiO‐YSZ porous anode, and a 80 μm‐thick dense electrolyte with a gradient of composition: 10GDC on the cathode side to prevent the apparition of the La2Zr2O7 insulating phase and 8YSZ on the anode side to avoid the reduction of 10GDC with the fuel gas. Power densities present promising performances (319 mW cm−2 at 830 °C) given that electrolyte thickness and electrochemical system measurement may be improved. [ABSTRACT FROM AUTHOR]

All solid‐state batteries (ASSB) are the next generation of safe and high‐energy‐density energy storage technology. Their development is currently impeded by the stability issues of solid‐state electrolyte (SSE) limiting the creation of interfaces of quality high enough to ensure efficient transfer of charges. The garnet Li7−xLa3Zr2−xTaxO12 (LLZO:Ta) is one of the most appealing oxide‐based SSE but its high sensitivity to moist air engenders difficulties in designing process to densify and assemble components of the ASSB. Based on a careful investigation of LLZO:Ta thermal and chemical stability, a heat treatment is designed and shown to fully reverse the protonation process. The investigation of spark plasma sintering protocols confirms that pretreated LLZO:Ta can be densified at a temperature as low as 850 °C or with a short duration (few seconds) at 900 °C. The characterization of obtained ceramics shows conductivities close to the bulk properties and confirms the absence of influence of grain boundaries. The study of composite electrodes shows that LLZO:Ta is suitable to act both as SSE separator and ionic percolator in positive electrode, the selection of active material remains the main issue to target self‐standing Li‐based ASSB. [ABSTRACT FROM AUTHOR]

MXenes, a rapidly growing family of 2D transition metal carbides, carbonitrides, and nitrides, are one of the most promising high‐rate electrode materials for energy storage. Despite the significant progress achieved, the MXene synthesis process is still burdensome, involving several procedures including preparation of MAX, etching of MAX to MXene, and delamination. Here, a one‐pot molten salt electrochemical etching (E) method is proposed to achieve Ti2C MXene directly from elemental substances (Ti, Al, and C), which greatly simplifies the preparation process. In this work, different carbon sources, such as carbon nanotubes (CNT) and reduced graphene oxide (rGO), are reacted with Ti and Al micro‐powders to prepare Ti2AlC MAX with 1D and 2D tuned morphology followed by in situ electrochemical etching from Ti2AlC MAX to Ti2CTx MXene in low‐cost LiCl‐KCl. The introduction of the O surface group via further ammonium persulfate (APS) treatment can act in concert with Cl termination to activate the pseudocapacitive redox reaction of Ti2CClyOz in the non‐aqueous electrolyte, resulting in a Li+ storage capacity of up to 857 C g−1 (240 mAh g−1) with a high rate (86 mAh g−1 at 120 C) capability, which makes it promising for use as an anode material for fast‐charging batteries or hybrid devices in a non‐aqueous energy storage application. [ABSTRACT FROM AUTHOR]

The garnet Li 7-x La 3 Zr 2-x Ta x O 12 (LLZTO) has attracted a real scientific interest in the last decade as it is one of the safest solid-state electrolytes for next generation high energy lithium batteries. However, its elaboration requires several steps from phase stabilization to densification of the part. This final step, with long and high temperature treatment induces lithium loss due to sublimation. Electric arc-melting allows short time elaboration of dense parts in one-step, eventually minimizing Li sublimation. Thus, the synthesis by arc-melting of LLZTO is exposed here. Stabilized phases and microstructures are studied depending on chemical composition and casting parameters. The direct obtaining of dense parts instead of powder allows better moisture stability thanks to fast growth of protective layer preventing in-depth penetration of the H+/Li+ exchange. Finally, ionic conductivity of fused parts is in a similar range to sintered pellets produced using Spark Plasma Sintering with powdered fused parts. Those results confirm the interest of electric arc-melting synthesis as an alternative LLZTO elaboration. • Fused raw powders are cast to obtain dense cubic LLZO with only 0.4 Ta pfu. • Thickness of cast samples can be tuned. • Grains >50 μm in diameter are stabilized with homogeneous repartition of elements. • Ground powder can be processed by SPS. [ABSTRACT FROM AUTHOR]

This study investigates mechanochemical synthesis and cation-disordering mechanism of wurtzite-type Li 3 VO 4 (LVO), highlighting its promise as a high-performance anode material for lithium-ion batteries and hybrid supercapacitors. Mechanochemical treatment of pristine LVO using a high-energy ball mill results in a "pure cation-disordered" LVO phase, allowing for meticulous analysis of cation arrangement. The X-ray and neutron diffraction study demonstrates progressive loss of order in LVO crystal with increasing milling duration. High-resolution transmission electron microscopy reveals disrupted lattice fringes, indicating cationic misalignment. Pair-distribution function analysis confirms loss of cation arrangements and the presence of short-range order. Combination of these multiple analytical techniques achieves a comprehensive understanding of cation regularity and clearly demonstrates order/disorder dichotomy in cation-disordered materials, ranging from short (<8 Å) to middle-long range (8-30 Å), using an integrated superstructure model of the cation-disordered LVO crystals. Electrochemical testing reveals that mechanochemically treated LVO exhibits superior rate capability, with a 70% capacity retention at a high current density of 50C-rate. Lithium diffusion coefficient measurements demonstrate enhanced lithium-ion mobility in the mechanochemically treated LVO, attributed to cation-disordering effect. These findings provide valuable insights into mechanochemical cation-disordering in LVO, presenting its potential as an efficient anode material for lithium-ion-based electrochemical energy storage., (© 2024 Wiley‐VCH GmbH.)

Perovskite-type oxides, characterized by excellent multifunctional physical and chemical properties, are widely used in ferroelectric, piezoelectric, energy conversion, and storage applications. It is shown here that the perovskite-type SrVO 3 can achieve excellent electrochemical performance as lithium-ion battery anodes thanks to its high electrically and ionically conductivity. Conducting additive-free SrVO 3 electrodes can deliver a high specific capacity of 324 mAh g -1 at a safe and low average working potential of ≈0.9 V vs Li/Li + together with excellent high-rate performance. A high areal capacity of ≈5.4 mAh cm -2 is obtained using an ultrathick (≈120 μm) electrode. Moreover, the fully lithiated SrVO 3 electrode exhibits only 2.3% volume expansion that is explained by a simple solid-solution Li + -storage mechanism, resulting in good cycling stability of the electrode. This study highlights the perovskite-type SrVO 3 as a promising Li + -storage anode and provides opportunities for exploring a variety of perovskite oxides as next-generation metal-ion battery anodes., (© 2021 Wiley-VCH GmbH.)

Highly-dispersed 10 wt% FePO 4 (FP)-coated LiCo 0.90 Ti 0.05 PO 4 (LCTP) was successfully synthesized within a multiwalled carbon nanotube matrix via our original ultracentrifugation process. 10 wt% FP-coated LCTP sample showed a higher discharge capacity of 116 mA h g -1 together with stable cycle performance over 99% of capacity retention at the 100 th cycle in high voltage. A combination of TEM, XRD, XPS, and XAFS analyses suggests that (i) Ti 4+ -substitution increases the utilization of Co redox (capacity increase) in LCP crystals by suppressing the Co 3 O 4 formation and creating the vacancies in Co sites, and (ii) the FP-coating brought about the Fe enrichment of the surface of LCTP which prevents an irreversible crystal structure change and electrolyte decomposition during cycling, resulting in the stable cycle performance., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)