고성능 및 내구성이 뛰어난 가역 프로토닉 세라믹 전지용 Sr/Co-Free 공기극

성보석(Boseok Seong),최시혁(Sihyuk Choi) 대한기계학회 2024 대한기계학회 춘추학술대회 Vol.2024 No.4

pn-Heterojunction Effects of Perylene Tetracarboxylic Diimide Derivatives on Pentacene Field-Effect Transistor

Yu, Seong Hun,Kang, Boseok,An, Gukil,Kim, BongSoo,Lee, Moo Hyung,Kang, Moon Sung,Kim, Hyunjung,Lee, Jung Heon,Lee, Shichoon,Cho, Kilwon,Lee, Jun Young,Cho, Jeong Ho American Chemical Society 2015 ACS APPLIED MATERIALS & INTERFACES Vol.7 No.3

<P>We investigated the heterojunction effects of perylene tetracarboxylic diimide (PTCDI) derivatives on the pentacene-based field-effect transistors (FETs). Three PTCDI derivatives with different substituents were deposited onto pentacene layers and served as charge transfer dopants. The deposited PTCDI layer, which had a nominal thickness of a few layers, formed discontinuous patches on the pentacene layers and dramatically enhanced the hole mobility in the pentacene FET. Among the three PTCDI molecules tested, the octyl-substituted PTCDI, PTCDI-C<SUB>8</SUB>, provided the most efficient hole-doping characteristics (p-type) relative to the fluorophenyl-substituted PTCDIs, 4-FPEPTC and 2,4-FPEPTC. The organic heterojunction and doping characteristics were systematically investigated using atomic force microscopy, 2D grazing incidence X-ray diffraction studies, and ultraviolet photoelectron spectroscopy. PTCDI-C<SUB>8</SUB>, bearing octyl substituents, grew laterally on the pentacene layer (2D growth), whereas 2,4-FPEPTC, with fluorophenyl substituents, underwent 3D growth. The different growth modes resulted in different contact areas and relative orientations between the pentacene and PTCDI molecules, which significantly affected the doping efficiency of the deposited adlayer. The differences between the growth modes and the thin-film microstructures in the different PTCDI patches were attributed to a mismatch between the surface energies of the patches and the underlying pentacene layer. The film-morphology-dependent doping effects observed here offer practical guidelines for achieving more effective charge transfer doping in thin-film transistors.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/aamick/2015/aamick.2015.7.issue-3/am507854s/production/images/medium/am-2014-07854s_0009.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/am507854s'>ACS Electronic Supporting Info</A></P>

Inverse Transfer Method Using Polymers with Various Functional Groups for Controllable Graphene Doping

Lee, Seong Kyu,Yang, Jae Won,Kim, Hyun Ho,Jo, Sae Byeok,Kang, Boseok,Bong, Hyojin,Lee, Hyo Chan,Lee, Geunsik,Kim, Kwang S.,Cho, Kilwon American Chemical Society 2014 ACS NANO Vol.8 No.8

<P>The polymer-supported transfer of chemical vapor deposition (CVD)-grown graphene provides large-area and high-quality graphene on a target substrate; however, the polymer and organic solvent residues left by the transfer process hinder the application of CVD-grown graphene in electronic and photonic devices. Here, we describe an inverse transfer method (ITM) that permits the simultaneous transfer and doping of graphene without generating undesirable residues by using polymers with different functional groups. Unlike conventional wet transfer methods, the polymer supporting layer used in the ITM serves as a graphene doping layer placed at the interface between the graphene and the substrate. Polymers bearing functional groups can induce n-doping or p-doping into the graphene depending on the electron-donating or -withdrawing characteristics of functional groups. Theoretical models of dipole layer-induced graphene doping offered insights into the experimentally measured change in the work function and the Dirac point of the graphene. Finally, the electrical properties of pentacene field effect transistors prepared using graphene electrodes could be enhanced by employing the ITM to introduce a polymer layer that tuned the work function of graphene. The versatility of polymer functional groups suggests that the method developed here will provide valuable routes to the development of applications of CVD-grown graphene in organic electronic devices.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/ancac3/2014/ancac3.2014.8.issue-8/nn503329s/production/images/medium/nn-2014-03329s_0006.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nn503329s'>ACS Electronic Supporting Info</A></P>

Study on design for herbal monograph

Chul Kim,Boseok Seong,Sang-Jun Yea,Yunji Jang 한국콘텐츠학회 2015 한국콘텐츠학회 ICCC 논문집 Vol.- No.-

An OASIS advancement strategy through user needs analysis

yunji Jang,Chul Kim,Boseok Seong,Sangjun Yea 한국콘텐츠학회 2017 한국콘텐츠학회 ICCC 논문집 Vol.2017 No.12

Atomically Thin Epitaxial Template for Organic Crystal Growth Using Graphene with Controlled Surface Wettability

Nguyen, Nguyen Ngan,Jo, Sae Byeok,Lee, Seong Kyu,Sin, Dong Hun,Kang, Boseok,Kim, Hyun Ho,Lee, Hansol,Cho, Kilwon American Chemical Society 2015 NANO LETTERS Vol.15 No.4

<P>A two-dimensional epitaxial growth template for organic semiconductors was developed using a new method for transferring clean graphene sheets onto a substrate with controlled surface wettability. The introduction of a sacrificial graphene layer between a patterned polymeric supporting layer and a monolayer graphene sheet enabled the crack-free and residue-free transfer of free-standing monolayer graphene onto arbitrary substrates. The clean graphene template clearly induced the quasi-epitaxial growth of crystalline organic semiconductors with lying-down molecular orientation while maintaining the “wetting transparency”, which allowed the transmission of the interaction between organic molecules and the underlying substrate. Consequently, the growth mode and corresponding morphology of the organic semiconductors on graphene templates exhibited distinctive dependence on the substrate hydrophobicity with clear transition from lateral to vertical growth mode on hydrophilic substrates, which originated from the high surface energy of the exposed crystallographic planes of the organic semiconductors on graphene. The optical properties of the pentacene layer, especially the diffusion of the exciton, also showed a strong dependency on the corresponding morphological evolution. Furthermore, the effect of pentacene–substrate interaction was systematically investigated by gradually increasing the number of graphene layers. These results suggested that the combination of a clean graphene surface and a suitable underlying substrate could serve as an atomically thin growth template to engineer the interaction between organic molecules and aromatic graphene network, thereby paving the way for effectively and conveniently tuning the semiconductor layer morphologies in devices prepared using graphene.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/nalefd/2015/nalefd.2015.15.issue-4/nl504958e/production/images/medium/nl-2014-04958e_0008.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nl504958e'>ACS Electronic Supporting Info</A></P>

Graphene growth under Knudsen molecular flow on a confined catalytic metal coil.

Bong, Hyojin,Jo, Sae Byeok,Kang, Boseok,Lee, Seong Kyu,Kim, Hyun Ho,Lee, Seung Goo,Cho, Kilwon RSC Pub 2015 Nanoscale Vol.7 No.4

<P>We have established a simple method for drastically improving the productivity of chemical vapor deposition in large-area graphene synthesis using a roll-stacked Ni coil as a catalyst. Our systematic investigation of the effects of a confined catalytic geometry has shown that the gas flow through interfacial gaps within the stack follows non-continuum fluid dynamics when the size of the gap decreases sufficiently, which enhances the dissolution of the carbon sources into the catalyst during synthesis. Quantitative criteria for graphene growth in the confined geometry are established through the introduction of the Knudsen number, Kn, which is the ratio of the mean-free-path of the gas molecules to the size of the gap. The criteria provided in this article for the synthesis of graphene in the confined geometry are expected to provide the foundations for the efficient mass production of large-area graphene. We also show that the evolution of the catalytic Ni surface in a stacked system results in larger grains in the (111) plane, and consequently in reproducible, uniform, and high-quality multi-layered graphene.</P>

Transcriptome analysis demonstrating the therapeutic effect of Tenodera angustipennis (Mantidis Ootheca) extracts on radiation‐induced gonadal toxicity in mouse testis

Kim Chul,Kim Joong Sun,Lee Hae June,Seong Boseok,Seo Seung‐won,Son Hyojung,Jeon Ji‐Hyeon,Shin Younhee 한국곤충학회 2022 Entomological Research Vol.52 No.7

Mantidis Ootheca (MO) is the egg case of the praying mantis. MO has been used in Oriental and Chinese traditional medicine in a steamed form and is known for enhancing male fertility since ancient times. Here, we used total RNA sequencing to reveal the genome-wide differential expression profiles of mice subjected to irradiation and Tenodera angustipennis MO extract treatment to understand the therapeutic effect of MO extract on radiation-induced gonadal toxicity in mice. Approximately 225 genes exhibited differential expression patterns, among which 24 showed a reversal of expression pattern in response to irradiation and MO extract treatment. Most of these genes are associated with spermatogenesis and could be considered as candidates for further experimental studies. Considering that there is no approved radio-protective drug for treating radiation-induced damage to testicles, we would like to demonstrate the therapeutic potential of the use of MO extract as a traditional medicinal practice that can serve as a one of tool for the mitigation and treatment of gonadal toxicity.