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Chemical solution deposition (CSD)-based thin-film fabrication techniques for solid electrolytes are important for accelerating the commercialization of all-solid-state lithium-ion batteries. Post-treatments, typically heat treatments at high temperatures, are applied to obtain a pure crystal structure with a dense morphology for high electrochemical performance. However, lithium evaporates at high temperatures, leading to changes in the material composition and decrease in performance. In this study, a novel rapid sintering method, namely flash-light sintering (FLS), was applied as a post-treatment for spin-coated lithium lanthanum titanate (LLTO) thin films to prevent lithium evaporation and obtain fully dense thin films with perovskite structures. The flash-light-sintered LLTO thin film exhibited negligible lithium loss with pore-free morphologies and a pure cubic perovskite structure, whereas the thermally sintered LLTO thin film exhibited significant lithium evaporation. The lithium-preserved cubic LLTO dense thin films prepared by FLS showed an outstanding total ionic conductivity of ∼6 × 10−5 S cm−1, the highest recorded for CSD-based LLTO thin films. We demonstrated that the FLS method could be successfully applied for LLTO thin-film fabrication while maintaining the lithium stoichiometry and ensuring a highly densified film and cubic structure, which has a higher ionic conductivity than those of structures such as tetragonal or orthorhombic unit cells. The rapid FLS method not only simplifies the fabrication of LLTO thin films but also provides opportunities for its wide application to materials containing lithium or other elements with low melting points. [ABSTRACT FROM AUTHOR]

This paper examines whether mandatory Korean International Financial Reporting Standards (K‐IFRS) adoption in Korea reduces initial public offering (IPO) underpricing. We find that IPO underpricing has increased following the mandatory adoption of K‐IFRS in 2011. We also show that this relation is more pronounced for non‐chaebol firms, firms not backed by venture capital, and firms in concentrated industries. This suggests that the negative impact of K‐IFRS adoption is concentrated on the firms with a greater pre‐adoption information asymmetry. Our results indicate that some policy consideration is needed in order to help investors adapt to the newly adopted standards, especially to those related to firms seeking to go public. [ABSTRACT FROM AUTHOR]

This article provides evidence that firms with high market expectations disclose more information to investors, utilizing the fair disclosure regulation in Korea to proxy for their disclosure choices. This finding is consistent with the argument that in order to retain their dominant positions, highly evaluated firms are more concerned about the market's perception of them as providers of timely and detailed disclosure. We also find that the impact of market expectations on disclosure is more pronounced for chaebol firms. Combined with prior research on the relationship between firm performance and voluntary disclosure, we provide important implications for the determinants of corporate disclosure [ABSTRACT FROM AUTHOR]

In this study, scandia-stabilized zirconia (ScSZ) electrolyte thin-film layers were deposited via chemical solution deposition (CSD). We selected 10ScSZ (10% Sc 2 O 3 , 90% ZrO 2 molar ratio) as the target material, and the precursor solution was prepared by precise calculations. The 10ScSZ solution was deposited on Al2O3 substrate using a spin-coating method. Then, the substrate was sintered using two methods: flash light irradiation and thermal. The characteristics of the thin films were compared, including ionic conductivity, surface morphology, and chemical composition. Pulsed light sintering was applied in the sintering step under a variety of energy density conditions from 80 to 130 J/ cm 2 , irradiation on/off times of 10 ms and 10 ms/500 ms, number of pulses, and bottom heat from 300 to 600 °C. The ionic conductivity of the ScSZ electrolyte layers fabricated by thermal or flash light irradiation methods was tested and compared. The results show that the ScSZ electrolyte layer sintered by flash light irradiation within a few seconds of process time had similar ionic conductivity to the electrolyte layer that was thermal sintered for about 10 h including cooling process. [ABSTRACT FROM AUTHOR]