Publications by authors named "Heeseon Lim"

Light absorption in organic molecules on an inorganic substrate and subsequent electron transfer to the substrate create so-called hybrid charge transfer exciton (HCTE). The relaxation process of the HCTE states largely determines charge separation efficiency or optoelectronic device performance. Here, the study on energy and time-dispersive behavior of photoelectrons at the hybrid interface of copper phthalocyanine (CuPc)/p-GaAs(001) upon light excitation of GaAs reveals a clear pathway for HCTE relaxation and delayed triplet-state formation.

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Organic crystals deposited on 2-dimensional (2D) van der Waals substrates have been widely investigated due to their unprecedented crystal structures and electrical properties. van der Waals interaction between organic molecules and the substrate induces epitaxial growth of high quality organic crystals and their anomalous crystal morphologies. Here, we report on unique ambipolar charge transport of a "lying-down" pentacene crystal grown on a 2D hexagonal boron nitride van der Waals substrate.

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We confirmed the coverage dependent variation of tautomers of 2-mercaptothiazoline (the thiolate and thione forms) adsorbed on the Ge(100) surface under UHV conditions by using HRXPS measurements in conjunction with the DFT calculation method, which was studied before only in aqueous systems. The C 1s, S 2p, and N 1s core-level spectra obtained using HRXPS revealed the simultaneous presence of two distinct adsorption structures in different proportions at both low (0.15 ML) and high (0.

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