• Journal of the Korean Vacuum Society
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• v.17 no.5
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• pp.394-399
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• 2008

Growth and electronic structure of pentacene film on silicon oxide before and after octadecyltrichlorosilane (OTS) treatment have been studied by photoelectron spectroscopy and photoelectron emission microscopy. On the OTS-treated surface, due to the weak interaction between the substrate and pentacene, the diffusion of pentacene is enhanced and domain size gradually grows, leading to a gradual change of the HOMO offset position. On the bare silicon oxide, the change of the HOMO position is marginal because of relatively strong interaction between the substrate and pentacene from the beginning.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2016.11a
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• pp.97-97
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• 2016

Development of advanced Li-ion battery cells with high durability is critical for safe operation, especially in applications to electric vehicles and portable electronic devices. Understanding fundamental mechanism on the formation of a solid-electrolyte interphase (SEI) layer, which plays a substantial role in the electrochemical stability of the Li-ion battery, in a cathode was rarely reported unlike in an anode. Using first-principles density functional theory (DFT) calculations and ab-initio molecular dynamic (AIMD) simulations we demonstrate atomic-level process on the generation of the SEI layer at the interface of a carbonate-based electrolyte and a spinel $LiMn_2O_4$ cathode. To accomplish the object we calculate the energy band alignment between the work function of the cathode and frontier orbitals of the electrolyte. We figure out that a proton abstraction from the carbonate-based electrolyte is a critical step for the initiation of an SEI layer formation. Our results can provide a design concept for stable Li-ion batteries by optimizing electrolytes to form proper SEI layers.