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The development of cathode materials for lithium-ion batteries (LIBs) aims to achieve high energy density, cost-effectiveness, and thermal as well as mechanical stability. It generally proceeds through multidimensional design rules at the atomic, phase, particle, and electrode levels. Recently, new strategies have been proposed to achieve high energy density even in olivine-structured cathodes, which have a relatively lower theoretical capacity compared to layered cathode materials. These strategies involve substituting iron (Fe) with manganese (Mn), controlling particle morphology, and fabricating thick electrodes to simultaneously achieve high energy density and cost-effectiveness. However, comprehensive design guidelines for the material design, particle morphology, and fabrication of thick electrodes for olivine cathodes are still lacking. Herein, we provide detailed insights from well-established prior knowledge on olivine cathodes and share the latest findings related to their particle morphology control and electrode thickening. Additionally, our review closely investigates further considerations related to kinetics, such as low electronic and ionic conductivity, and mechanical instability issues that arise while thickening electrodes. It is emphasized that these issues can be resolved through a comprehensive understanding and strategies from the atomic level to the electrode level. Therefore, this review aims to contribute to achieving high energy density in olivine-based cathodes by understanding their kinetic limitations and mechanical instabilities. [ABSTRACT FROM AUTHOR]

Ni‐rich layered oxides are envisioned as the most promising cathode materials for next‐generation lithium‐ion batteries; however, their practical adoption is plagued by fast capacity decay originating from chemo‐mechanical degradation. The intrinsic chemical–mechanical instability, inherited from atomic‐ and nanoscale defects generated during synthesis, is not yet resolved. Here, atomic‐ and nanoscale structural evolution during solid‐state synthesis of Ni‐rich layered cathode, Li[Ni0.92Co0.03Mn0.05]O2, is investigated using combined X‐ray/neutron scattering and electron/X‐ray microscopy. The multiscale analyses demonstrate the intertwined correlation between phase transition and microstructural evolution, with atomic‐scale defects derived from the decomposition of precursors leading to the creation of intra/inter‐granular pores. The nucleation and coalescence mechanism of pore defects during the synthesis of Ni‐rich layered cathodes are quantitatively revealed. Furthermore, a modified synthetic route is proposed to effectively circumvent the formation of nanoscale defects in Ni‐rich layered cathodes by facilitating uniform synthetic reactions, resulting in superior electrochemical and microstructural stability. [ABSTRACT FROM AUTHOR]

Redox-active organic materials have recently drawn significant attention in the development of green and cost-efficient rechargeable batteries. However, their use as a cathode has been practically hampered in part by the relatively low redox potentials that are typically displayed at ∼2 V (vs. Li/Li+). Herein, we report a rationally designed oxygen-containing heterocyclic compound, dibenzo-1,4-dioxin (DD), which undergoes a reversible redox reaction at the highest redox potential (1.1 V vs. Ag/Ag+ or 4.1 V vs. Li/Li+) among organic electrode materials reported thus far. Moreover, DD, a ready-to-charge active material, delivers a flat discharge voltage profile at this high voltage of 4.1 V in a lithium cell with a respectable rate capability. From a combined spectroscopic and computational analysis, it is revealed that the primary redox reaction takes place via the redox activity of the ring-embedded oxygen based on the p-type reaction in a dual-ion battery. We further demonstrate that introducing an iptycene motif to DD substantially suppresses the dissolution of the electrode material, enhancing the cycle stability without compromising the high discharge voltage. This finding suggests that a practically high discharge voltage over 4 V (vs. Li/Li+) can be achievable from the organic materials by the rational molecular tuning of redox-active atoms and the molecular skeleton, opening up a pathway for developing high-voltage organic batteries. [ABSTRACT FROM AUTHOR]

Herein, the self‐reinforced inductive effect derived from coexistence of both p‐ and n‐type redox‐active motifs in a single organic molecule is presented. Molecular orbital energy levels of each motif are dramatically tuned, which leads to the higher oxidation and the lower reduction potentials. The self‐reinforced inductive effect of the symmetric bipolar organic molecule, N,N'‐dimethylquinacridone (DMQA), is corroborated, by both experimental and theoretical methods. Furthermore, its redox mechanism and reaction pathway in the Li+‐battery system are scrutinized. DMQA shows excellent capacity retention at the operating voltage of 3.85 and 2.09 V (vs Li+/Li) when used as the cathode and anode, respectively. Successful operation of DMQA electrodes in a symmetric all‐organic battery is also demonstrated. The comprehensive insight into the energy storage capability of the symmetric bipolar organic molecule and its self‐reinforced inductive effect is provided. Thus, a new class of organic electrode materials for symmetric all‐organic batteries as well as conventional rechargeable batteries can be conceived. [ABSTRACT FROM AUTHOR]

We use CeO x -TiO2 hetero-interfaces generated on the surface of CeO x -TiO2 hybrid oxide supporting powders to stabilize Au single-atoms (SAs) with excellent low-temperature activity toward CO oxidation. Based on intriguing density functional theory calculation results on the preferential formation of Au-SAs at the CeO x -TiO2 interfaces and the high activity of Au-SAs toward the Marsâ€"van Krevelen type CO oxidation, we synthesized a Au/CeO x -TiO2 (ACT) catalyst with 0.05 wt.% of Au content. The Au-SAs stabilized at the CeO x -TiO2 interfaces by electronic coupling between Au and Ce showed improved low-temperature CO oxidation activity than the conventional Au/TiO2 control group catalyst. However, the light-off profile of ACT showed that the early activated Au-SAs are not vigorously participating in CO oxidation. The large portion of the positive effect on the overall catalytic activity from the low activation energy barrier of ACT was retarded by the negative impact from the decreasing active site density at high temperatures. We anticipate that the low-temperature activity and high-temperature stability of Au-SAs that stand against each other can be optimized by controlling the electronic coupling strength between Au-SAs and oxide clusters at the Au-oxide-TiO2 interfaces. Our results show that atomic-precision interface modulation could fine-tune the catalytic activity and stability of Au-SAs. [ABSTRACT FROM AUTHOR]

Four types of slip systems (basal , prismatic , pyramidal , and pyramidal ) and two types of twinning (extension twinning {10 1 – 2} and contraction twinning {10 1 – 1}) could be identified in magnesium alloys using scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD). In addition, the Schmid factors (SF) of these slip systems were systematically calculated on the basis of the Euler angle which was obtained in EBSD. The identification of slip systems and calculation of SF can help us to understand the contribution made by each type of slip in the plastic deformation of the material, which is important for understanding the deformation mechanism. [ABSTRACT FROM AUTHOR]