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Garnet‐type solid‐state electrolytes are among the most reassuring candidates for the development of solid‐state lithium metal batteries (SSLMB) because of their wide electrochemical stability window and chemical feasibility with lithium. However, issues such as poor physical contact with Li metal tend to limit their practical applications. These problems were addressed using β‐SiC as an additive to the Li anode, resulting in improved wettability over Li6.75La3Zr1.75Ta0.25O12 (LLZTO) and establishing an improved interfacial contact. At the Li–SiC|LLZTO interface, intimacy was induced by a lithiophilic Li4SiO4 phase, whereas robustness was attained through the hard SiC phase. The optimized Li–SiC|LLZTO|Li–SiC symmetric cell displayed a low interfacial impedance of 10 Ω cm2 and superior cycling stability at varying current densities up to 5800 h. Moreover, the modified interface could achieve a high critical current density of 4.6 mA cm−2 at room temperature and cycling stability of 1000 h at 3.5 mA cm−2. The use of mechanically superior materials such as SiC as additives for the preparation of a composite anode may serve as a new strategy for robust garnet‐based SSLMB. [ABSTRACT FROM AUTHOR]

All‐solid‐state batteries with solid ionic conductors packed between solid electrode films can release the dead space between them, enabling a greater number of cells to stack, generating higher voltage to the pack. This Review is focused on using high‐voltage cathode materials, in which the redox peak of the components is extended beyond 4.7 V. Li−Ni−Mn−O systems are currently under investigation for use as the cathode in high‐voltage cells. Solid electrolytes compatible with the cathode, including halide‐ and sulfide‐based electrolytes, are also reviewed. Discussion extends to the compatibility between electrodes and electrolytes at such extended potentials. Moreover, control over the thickness of the anode is essential to reduce solid‐electrolyte interphase formation and growth of dendrites. The Review discusses routes toward optimization of the cell components to minimize electrode‐electrolyte impedance and facilitate ion transportation during the battery cycle. [ABSTRACT FROM AUTHOR]

The design of high‐energy‐density batteries is the future goal of research on Li‐ion batteries. Halide‐type solid‐state electrolytes (SSEs) exceed their counterparts in terms of their stability at high potential. In this minireview, we discuss the developments in the work on halide‐type SSEs for all‐solid‐state Li batteries. In particular, we focus on the Li3InCl6 structure. The effect of synthesis routes on this structure, as well as the convertible products resulting from its phase changes, is discussed. Conductivity can be increased and the electrochemical window can be improved through doping with different materials. Our review aims to provide readers with an overview of the stability and degradation of Li3InCl6 SSE and the structure of halide‐type SSEs (Li–M–X, where M is a metal and X is a halogen). [ABSTRACT FROM AUTHOR]

Limiting the carbon emission to the atmosphere requires the efficient utilization of carbonaceous gases and their capture via well‐designed platforms. Metal–CO2 batteries are currently being demonstrated as the route to utilize CO2 and produce energy simultaneously. In particular, Na–CO2 batteries are considered an alternative to Li‐batteries because of their abundance and low cost. In the current review, the developments in the field of Na–CO2 batteries are discussed. Carbon dioxide reactions to the decomposition of discharge products have been discussed elaborately. The main discharge products of Na–CO2 batteries are Na2CO3 and C. In the current review, various strategies are discussed to decompose the discharge products and hence improve cycle stability. The fraction of CO2 has a substantial influence on cell cycles. A plausible route of battery reaction can be drawn with the help of an ex situ analysis of the electrodes. The final part of the review focuses on the use of solid‐state Na‐ion conductors in Na–CO2 batteries. [ABSTRACT FROM AUTHOR]

Near‐infrared (NIR) phosphors have gained a substantial amount of attention in the past few years simply due to their numerous applications. Recent publications have reported interesting findings regarding the fundamentals of phosphors. However, the unclear application of these phosphors limits their potential. This mini review aims to provide insights for researchers regarding the potential applications of NIR phosphors and their perspectives for further development of NIR phosphor technology. [ABSTRACT FROM AUTHOR]

Li–air batteries are limited to lab‐scale research owing to the uninterrupted formation of discharge products. In the case of Li–CO2 batteries, the increase in overpotential caused by Li2CO3 formation results in cell death. In this study, Cu2O crystals having three different types of shapes (i.e., cubic, octahedral, and rhombic) were synthesized to compare their catalytic activity toward CO2 reactions. The full‐cycle and long‐term stability test revealed that rhombohedral Cu2O facilitates Li2CO3 decomposition more efficiently than that of cubic and octahedral Cu2O. The cycle was extended to investigate the photocatalytic activity of the rhombic Cu2O by illuminating the cell. The repeated cycles to 1 h showed a maximum overpotential of 1.5 V, which is 0.5 V lower than that of the cell without illumination. A postmortem analysis of the cell after dividing the cycles into segments demonstrated interesting results concerning the role of light and Cu2O during the cell cycle. [ABSTRACT FROM AUTHOR]

Development of a solar water splitting device requires design of a low-cost, efficient, and non-noble metal compound as alternative to noble metals. For the first time, we showed that CoSe2 can function as co-catalyst in phototoelectrochemical hydrogen production. We designed a heterostructure of p-Si and marcasite-type CoSe2 for solar-driven hydrogen production. CoSe2 successively coupled with p-Si can act as a superior photocathode in the solar-driven water splitting reaction. Photocurrents up to 9 mA cm−2 were achieved at 0 V vs. reversible hydrogen electrode. Electrochemical impedance spectroscopy showed that the high photocurrents can be attributed to low charge transfer resistance between the Si and CoSe2 interfaces and that between the CoSe2 and electrolyte interfaces. Our results suggest that this CoSe2 is a promising alternative co-catalyst for hydrogen evolution. [ABSTRACT FROM AUTHOR]

Blue, green, and yellow phosphors are obtained in the Sr1−xY0.98+xCe0.02Si4N7−xCx system (x=0→1). Decreases in thermal quenching barrier height with x result from a dominant neighboring‐cation effect, through which the replacement of Sr2+ by Y3+ reduces the covalency of CeN bonding. Green emission is observed from a cation‐segregated nanostructure of SrYSi4N7 and Y2Si4N6C domains in x=0.2–0.6 samples. [ABSTRACT FROM AUTHOR]

In this study, lithium phosphorus oxynitride (LiPON) thin films were deposited by radio frequency (r.f.) magnetron sputtering of a lithium phosphate (Li3PO4) target with various powers. The crystal structure, morphology, chemical environment, ionic conductivity, electronic state and coordination type were sequentially characterized by X-ray diffraction, scanning electron microscope, X-ray photoelectron spectroscopy, electrochemical impedance spectroscopy and X-ray absorption spectroscopy, respectively. As the results, the optimal ionic conductivity was achieved by the r.f. power of 75 W. Furthermore, the P-N valence states of hybrid orbitals were increased with increasing the nitrogen amounts. [ABSTRACT FROM AUTHOR]

ABSTRACT A significant advance made in combinatorial approach research was that the emphasis shifted from simple mixing to intelligent screening, so as to improve the efficiency and accuracy of discovering new materials from a larger number of diverse compositions. In this study, the long-lasting luminescence of SrAl2O4, which is co-doped with Eu2+, Ce3+, Dy3+, Li+ and H3BO3, was investigated based on a combinatorial approach in conjunction with the Taguchi method. The minimal number of 16 samples to be tested (five dopants and four levels of concentration) were designed using the Taguchi method. The samples to be screened were synthesized using a parallel combinatorial strategy based on ink-jetting of precursors into an array of micro-reactor wells. The relative brightness of luminescence of the different phosphors over a particular period was assessed. Ce3+ was identified as the constituent that detrimentally affected long-lasting luminescence. Its concentration was optimized to zero. Li+ had a minor effect on long-lasting luminescence but the main factors that contributed to the objective property (long-lasting luminescence) were Eu2+, Dy3+ and H3BO3, and the concentrations of these dopants were optimized to 0.020, 0.030 and 0.300, respectively, for co-doping into SrAl2O4. This study demonstrates that the utility of the combinatorial approach for evaluating the effect of components on an objective property (e.g. phosphorescence) and estimating the expected performance under the optimal conditions can be improved by the Taguchi method. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]