A composite of a graphene oxide derivative as a novel sensing layer in an organic field-effect transistor

Kim, Yebyeol,An, Tae Kyu,Kim, Jiye,Hwang, Jihun,Park, Seonuk,Nam, Sooji,Cha, Hyojung,Park, Won Jeong,Baik, Jeong Min,Park, Chan Eon The Royal Society of Chemistry 2014 Journal of Materials Chemistry C Vol.2 No.23

<▼1><P>The receptor material (OA-GO)/polymeric semiconductor (F8T2) structure is newly introduced to active layer of OFET gas sensors and demonstrated to have better sensing ability than a comparable device with a polymer-only active layer.</P></▼1><▼2><P>We report the fabrication of a gas sensor with an oleylamine-modified graphene oxide (OA-GO)/poly(9-9′-dioctyl-fluorene-<I>co</I>-bithiophene) (F8T2) composite as an active layer and demonstrate that it has better sensing ability than a comparable device with an F8T2-only active layer. OA-GO was chosen as the receptor material because of its enhanced interaction with gas analytes and its easy mixing with F8T2. OA-GO was synthesized by a simple condensation reaction between GO and oleylamine (9-octadecylamine), and characterized by Fourier transform infrared spectroscopy. The sensitivities of the gas sensors with respect to acetone and ethanol analytes were investigated by measuring the electrical parameters of the corresponding organic field effect transistor at room temperature. The sensitivity of the OA-GO/F8T2 composite device was up to 34 times that of the F8T2 device for the mobility change of acetone.</P></▼2>

(Poly(3,4-ethylenedioxythiophene):Polystyrene Sulfonate):Polytetrafluoroethylene for Use in High-Performance and Stable Bottom-Contact Organic Field-Effect Transistors

Kim, Jiye,Kim, Hyekyoung,Kim, Se Hyun,Park, Chan Eon American Chemical Society 2016 The Journal of Physical Chemistry Part C Vol.120 No.2

<P>We successfully fabricated highly stable pentacene-based bottom-contact organic field-effect transistors (OFETs) with good charge injection properties at the electrode/organic semiconductor interface, obtained by optimizing the composition of solution-processed (poly(3,4-ethylenedioxythiophene):polystyrene sulfonate):polytetrafluoroethylene ((PEDOT:PSS):PTFE)-treated Au source/drain (S/D) electrodes. The (PEDOT:PSS):PTFE layer was deposited on the Au layer by spin-coating a mixture solution. The work function of the electrode increased from 4.84 to 5.21 eV as the PTFE concentration increased, accompanied by an interface dipole at the electrode surface. The optimized (PEDOT:PSS):PTFE (0.95:0.05)-treated electrodes significantly reduced the charge injection barrier at the electrode/semiconductor interface to achieve efficient charge transfer in the OFETs. Bottom-contact OFETs prepared with the optimized (PEDOT:PSS):PTFE-treated S/D electrodes had a field-effect mobility of 0.16 cm(2)/(V.s), which exceeded that of PEDOT:PSS-treated S/D electrodes (0.073 cm(2)/(V.s)). The operational stability of the optimized device was remarkable under gate-bias stress (V-G = -40 V over 3 h).</P>

Evaluation of thin-film nanocomposite RO membranes using TiO2 nanotubes and TiO2 nanoparticles: a comparative study

Kim, Jungchan,Baek, Youngbin,Hong, Sung Pil,Yoon, Hongsik,Kim, Seonghwan,Kim, Choonsoo,Kim, Jiye,Yoon, Jeyong Taylor Francis 2016 Desalination and Water Treatment Vol.57 No.51

Solitary Keratoacanthoma at the Recipient Site of a Full-Thickness Skin Graft: A Case Report and Review of the literature

Kim JeongHo,Lee Sang-Hoon,Kim Jiye,Hong Seung-Phil,Kim Sug Won 대한성형외과학회 2023 Archives of Plastic Surgery Vol.50 No.1

A 57-year-old man presented with a pigmented papule, 0.4 cm in diameter, on the left lower eyelid. Skin biopsy revealed a basal cell carcinoma, which was excised through a wide excision followed by a full-thickness skin graft (FTSG). Two weeks after the surgery, an erythematous nodule developed in the lower margin of the graft recipient site. The nodule size increased rapidly over 2 weeks, becoming dome-shaped with a central hyperkeratotic plug. A diagnosis of keratoacanthoma (KA) was made, and surgical excision was performed. Histological findings revealed a large, well-differentiated squamous tumor with a central keratin-filled crater and buttress. The HPV genotyping results were negative. Risk factors for KA include trauma, old age, exposure to UV radiation, immunosuppression, and HPV infection. KA has most often been reported to develop at the donor site. Although the pathogenesis of KA is unclear, trauma is believed to act as a second insult to a preceding oncogenic insult, such as exposure to UV radiation, resulting in a koebnerization. Herein, we report a case of solitary KA at a FTSG recipient site. This report presents information that may provide guidance during dermatologic surgeries.

Epidemiologic changes of facial bone fracture before and after coronavirus disease 2019: A level I trauma center in Korea

Kim JeongHo,Yang Chae Eun,Kim Sug Won,Kim Jiye 대한성형외과학회 2023 Archives of Plastic Surgery Vol.50 No.1

Background: The coronavirus disease 2019 (COVID-19) outbreak has had a major impact worldwide. Several countries have implemented restrictions on social interaction (“social distancing”). Several studies have reported that the epidemiology of trauma patients, such as those with facial bone fractures, has changed after COVID-19 pandemic. This study aimed to further explore these specific changes. Methods: This was a retrospective study of patients who presented to a single institution with facial bone fractures between January 1, 2016, and December 31, 2020. Baseline patient demographics, clinical information, type of fracture, etiology, and operative management were compared before and after COVID-19. Results: Of all cases, 3,409 occurred before COVID-19, and 602 occurred after COVID-19. Since the outbreak of COVID-19, the number of patients with facial fractures has not decreased significantly. A significant increase was noted in fractures that occurred outdoors (p<0.001). However, a decrease was observed in operative management between the groups (p<0.001). There was no significant difference in the proportion of assault, fall-down, industrial accident, or roll-down. In contrast, the proportion of traffic accidents and slip-down categories increased significantly (p<0.05). Moreover, a significant decrease was found in the proportion of the sports category (p=0.001) Conclusions: It was confirmed through this study that COVID-19 pandemic also affected epidemiology of facial fractures. Focusing on these changes, it is necessary to develop safety measures to reduce facial fractures.

Electrochemical Peroxodisulfate (PDS) Generation on a Self-Doped TiO₂ Nanotube Array Electrode

Kim, Jiye,Lee, Changha,Yoon, Jeyong American Chemical Society 2018 INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH - Vol.57 No.33

<P>Peroxodisulfate (PDS, S<SUB>2</SUB>O<SUB>8</SUB><SUP>2-</SUP>) is one of the strong oxidants (<I>E</I>°[S<SUB>2</SUB>O<SUB>8</SUB><SUP>2-</SUP>/HSO<SUB>4</SUB><SUP>-</SUP>] = 2.12 V<SUB>NHE</SUB>), which is widely used for radical polymerization or wastewater treatment. In electrochemical PDS generation, its efficiency highly depends on the •OH generating electrode materials. A boron-doped diamond (BDD) used in electrochemical PDS generation is very expensive prompting the need for new electrode materials for PDS generation. This study reports the self-doped TiO<SUB>2</SUB> nanotube array electrodes (blue and black TNAs) for PDS generation which are cheap and effective for generating a significant amount of •OH and comparable to BDD electrodes. Blue and black TNA electrodes were excellent for PDS generation exhibiting high current efficiencies for PDS generation (46% and 22%, respectively). Similar to the BDD electrode, it was also confirmed that •OH was the key precursor to the PDS generation on the self-doped TNA electrodes from the linear relationship between the PDS generation rate and •OH generation.</P> [FIG OMISSION]</BR>

Effects of tributyltin on thymic epithelial cells and T lymphocytes in the mouse thymus

Jiye Kim(김지예),Eunhyea Park(박은혜),Hanbig Lee(이한빛),Ahhyun Lee(이아현),Philjae Kim(김필재),Sojeong Park(박소정),Eunji Im(임은지),Hyunwon Yang(양현원) 환경독성보건학회 2015 한국독성학회 심포지움 및 학술발표회 Vol.2015 No.10

Capacitive and Oxidant Generating Properties of Black-Colored TiO₂ Nanotube Array Fabricated by Electrochemical Self-Doping

Kim, Choonsoo,Kim, Seonghwan,Lee, Jaehan,Kim, Jiye,Yoon, Jeyong American Chemical Society 2015 ACS APPLIED MATERIALS & INTERFACES Vol.7 No.14

<P>Recently, black-colored TiO<SUB>2</SUB> NTA (denoted as black TiO<SUB>2</SUB> NTA) fabricated by self-doping of TiO<SUB>2</SUB> NTA with the amorphous phase led to significant success as a visible-light-active photocatalyst. This enhanced photocatalytic activity is largely attributed to a higher charge carrier density as an effect of electrochemical self-doping resulting in a higher optical absorbance and lower transport resistance. Nevertheless, the potential of black TiO<SUB>2</SUB> NTA for other electrochemical applications, such as a supercapacitor and an oxidant-generating anode, has not been fully investigated. Here, we report the capacitive and oxidant generating properties of black TiO<SUB>2</SUB> NTA. The black TiO<SUB>2</SUB> NTA exhibited significantly a high value for areal capacitance with a good rate capability and novel electrocatalytic activity in generating <SUP>•</SUP>OHs and Cl<SUB>2</SUB> compared to pristine TiO<SUB>2</SUB> NTA with the anatase phase. This study suggests that the black TiO<SUB>2</SUB> NTA be applied as a supercapacitor and an oxidant generating anode.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/aamick/2015/aamick.2015.7.issue-14/acsami.5b00123/production/images/medium/am-2015-00123w_0008.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/am5b00123'>ACS Electronic Supporting Info</A></P>

Complementary photo and temperature cured polymer dielectrics with high-quality dielectric properties for organic semiconductors

Kim, Se Hyun,Jang, Mi,Kim, Jiye,Choi, Harim,Baek, Kyung-Youl,Park, Chan Eon,Yang, Hoichang The Royal Society of Chemistry 2012 Journal of materials chemistry Vol.22 No.37

<P>Photo and temperature cured polymer dielectrics could be fabricated on a gate-patterned glass, with two immiscible polymer precursors, divinyltetramethyldisiloxane-bis(benzocyclobutene) (BCB precursor) and poly(melamine-<I>co</I>-formaldehyde)acrylate (PMFA), which have excellent insulating properties, but show discernible dielectric constants and polarities. On hydrophobic BCB-assisted PMFA blend dielectrics (approximately 400 nm thick), organic field-effect transistors (OFET) and complementary inverters were demonstrated using pentacene and <I>N</I>,<I>N</I>′-ditridecylperylene-3,4,9,10-tetracarboxylic diimide (PTCDI-C13) as semiconducting channels. The values of field-effect mobilities showed up to 0.33 cm<SUP>2</SUP> V<SUP>−1</SUP> s<SUP>−1</SUP> (for pentacene) and 0.85 cm<SUP>2</SUP> V<SUP>−1</SUP> s<SUP>−1</SUP> (for PTCDI-C13), respectively. In addition, these based complementary inverter was successfully demonstrated with a high voltage gain of <I>ca.</I> 41, specifically, onto the 10 wt% BCB-assisted PMFA dielectric optimized to achieve a hydrophobic and smooth surface by vertically phase-separating the immiscible polymers.</P> <P>Graphic Abstract</P><P>Photo and temperature cured polymer dielectrics could be fabricated on a gate-patterned glass, with two immiscible polymer precursors, BCB and PMFA, which have excellent insulating properties, but show discernible dielectric constants and polarities. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c2jm33203e'> </P>

3D Hollow Framework Silver Nanowire Electrodes for High-Performance Bottom-Contact Organic Transistors

Kim, Jiye,Lee, So Hee,Kim, Haekyoung,Kim, Se Hyun,Park, Chan Eon American Chemical Society 2015 ACS APPLIED MATERIALS & INTERFACES Vol.7 No.26

<P>We successfully fabricated high performance bottom-contact organic field-effect transistors (OFETs) using silver nanowire (AgNW) network electrodes by spray deposition. The synthesized AgNWs have the dimensions of 40–80 nm in diameter and 30–80 μm in length and are randomly distributed and interconnected to form a 3D hollow framework. The AgNWs networks, deposited by spray coating, yield an average optical transmittance of up to 88% and a sheet resistance as low as 10 ohm/sq. For using AgNWs as source/drain electrodes of OFETs with a bottom-contact configuration, the large contact resistance at the AgNWs/organic channel remains a critical issue for charge injection. To enhance charge injection, we fabricate semiconductor crystals on the AgNW using an adsorbed residual poly(<I>N</I>-vinylpyrrolidone) layer. The resulting bottom-contact OFETs exhibit high mobility up to 1.02 cm<SUP>2</SUP>/(V s) and are similar to that of the top-contact Au electrodes OFETs with low contact resistance. A morphological study shows that the pentacene crystals coalesced to form continuous morphology on the nanowires and are highly interconnected with those on the channel. These features contribute to efficient charge injection and encourage the improvement of the bottom-contact device performance. Furthermore, the large contact area of individual AgNWs spreading out to the channel at the edge of the electrode also improves device performance.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/aamick/2015/aamick.2015.7.issue-26/acsami.5b02610/production/images/medium/am-2015-02610b_0011.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/am5b02610'>ACS Electronic Supporting Info</A></P>