PEDOT:PSS/GaN 하이브리드 접합 소자의 PEDOT:PSS 두께에 따른 I-V 특성

신민정,안형수,이삼녕 한국물리학회 2014 새물리 Vol.64 No.11

We fabricated a hybrid structure composed of an organic semiconductor poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) and an inorganic semiconductor GaN. PEDOT:PSS films with various thicknesses were deposited on to an n-GaN epilayer by using a spin coater, and the dependence of the current-voltage characteristics on the thickness of the PEDOT:PSS layer was examined. The PEDOT:PSS layer was homogeneously deposited on GaN epilayer, moreover the thickness of PEDOT:PSS layer was decreased by increasing the spin speed. An optimum device characteristic with the highest current-rectifying behavior was observed when the thickness of the PEDOT:PSS layer was about 125 nm. The relatively-high ideality factor (n $\sim$ 14) seemed to be associated with carrier tunneling or recombination at the hybrid interface due to the presence of various defects. 본 연구에서는 유기물 반도체인 PEDOT:PSS와 무기물 반도체인 GaN를 이용하여 하이브리드 구조를 제작하였다. 스핀 코팅 방법을 이용해 GaN 위에 다양한 두께를 가지는 PEDOT:PSS층을 제작하였고 PEDOT:PSS층의 두께에 의존하는 전류-전압 특성을 연구하였다. 단면 측정을 통해, PEDOT:PSS 층이 GaN 에피층 위에 빈틈없이 균일하게 증착되었을 뿐만 아니라, 코팅 속도가 증가함에 따라 두께가 점차적으로 감소함을 확인할 수 있었다. 또한 PEDOT:PSS가 약 125 nm의 두께 일 때 가장 좋은 다이오드 특성을 확인 할 수 있었고, 이때 캐리어의 터널링 및 소자 계면에 존재하는 결함들에 의해 큰 값을 가지는 이상계수 (n $\sim$ 14)를 관찰 할 수 있었다.

Preparation and characterization of poly(3,4-ethylenedioxythiophene) (PEDOT) using partially sulfonated poly(styrene-butadiene-styrene) triblock copolymer as a polyelectrolyte

김태영,김종은,김윤상,이태희,김원중,Kwang S. Suh 한국물리학회 2009 Current Applied Physics Vol.9 No.1

An aqueous dispersion of poly(3,4-ethylenedioxythiophene) (PEDOT) was prepared using a partially sulfonated poly(styrene-b-butadiene- b-styrene) (s-SBS) as a polyanion. For the preparation of s-SBS, poly(styrene-b-butadiene-b-styrene) was sulfonated to four different levels ranging from 44.1 to 64.8 mol%. These sulfonated polymers were characterized with IR spectroscopy and 1H NMR analysis to confirm sulfonation reaction. The preparation of the PEDOT complex was carried out through the chemical polymerization method in which the EDOT monomer starts to polymerize in the presence of s-SBS, resulting in an aqueous dispersion of PEDOT/s-SBS complex. The DC conductivities of PEDOT/s-SBS complexes were found to increase from 0.0003 to 0.05 s/cm as the sulfonation level of the corresponding s-SBS increases, which is consistent with the data recorded by UV–vis spectrophotometer. From the XPS experiments, it was concluded that the concentration of PEDOT-rich phase in the PEDOT/s-SBS increases as the sulfonation level of s-SBS increase, thus facilitating the charge transport along the doped PEDOT chains. An aqueous dispersion of poly(3,4-ethylenedioxythiophene) (PEDOT) was prepared using a partially sulfonated poly(styrene-b-butadiene- b-styrene) (s-SBS) as a polyanion. For the preparation of s-SBS, poly(styrene-b-butadiene-b-styrene) was sulfonated to four different levels ranging from 44.1 to 64.8 mol%. These sulfonated polymers were characterized with IR spectroscopy and 1H NMR analysis to confirm sulfonation reaction. The preparation of the PEDOT complex was carried out through the chemical polymerization method in which the EDOT monomer starts to polymerize in the presence of s-SBS, resulting in an aqueous dispersion of PEDOT/s-SBS complex. The DC conductivities of PEDOT/s-SBS complexes were found to increase from 0.0003 to 0.05 s/cm as the sulfonation level of the corresponding s-SBS increases, which is consistent with the data recorded by UV–vis spectrophotometer. From the XPS experiments, it was concluded that the concentration of PEDOT-rich phase in the PEDOT/s-SBS increases as the sulfonation level of s-SBS increase, thus facilitating the charge transport along the doped PEDOT chains.

“Drop-on-textile” patternable aqueous PEDOT composite ink providing highly stretchable and wash-resistant electrodes for electronic textiles

Kye, Min Jung,Cho, Jinhan,Yu, Jae Chul,Chang, Young-Wook,Han, Jihye,Lee, Eunji,Lim, Ho Sun,Lim, Jung Ah Elsevier 2018 Dyes and pigments Vol.155 No.-

<P><B>Abstract</B></P> <P>We demonstrate a direct-write patternable water-based poly (3,4-ethylenedioxythiophene): poly (styrene sulfonate) (PEDOT:PSS) composite ink which is capable of providing highly stretchable and washing-resistant electrodes on a fabric substrate for electronic textile applications. An aqueous composite ink consisting of PEDOT:PSS, graphene oxide nanosheets and anionic polyurethane does readily not permeated into hygroscopic fabric, which facilitate direct drawing of fine PEDOT electrode on the fabric without undesired blur effect. This limited permeation of aqueous PEDOT composite ink on the hygroscopic fabric is mainly originated from the intermolecular interactions of anionic polyurethane including hydrogen bonding with water molecules, and charge balancing interactions with PEDOT chains. Furthermore, addition of the graphene oxide nanosheets contributes to enhance the electrical conductivity of the composite by improving crystallization of PEDOT molecules. The PEDOT composite film shows unique structure of the PEDOT nanofibril network embedded by the polyurethane matrix, which resulted in an enough electrical pathway for charge carriers even though only 2.9 wt% of PEDOT:PSS existed in the composite film. The PEDOT composite film exhibited electrical conductivity of 4.6 S/cm, extremely high stretchability of 375% rupture strain, and high durability for repeated washing process with strong bleaching agent. Light emitting diode incorporated on the stretchable spandex with interconnects of the PEDOT composite pattern showed that LED light intensity was almost maintained even with stretching of PEDOT interconnects to 290%.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A direct patternable aqueous PEDOT:PSS composite ink providing stretchable and wash-resistant electrodes was demonstrated. </LI> <LI> Addition of graphene oxide and anionic polyurethane to PEDOT:PSS solution facilitate direct drawing of fine PEDOT electrode on the fabric. </LI> <LI> Limited permeation of aqueous PEDOT composite ink is originated from the intermolecular interactions of additives with PEDOT molecules. </LI> <LI> The PEDOT composite film shows unique structure of the PEDOT nanofibril network embedded by the polyurethane matrix. </LI> <LI> The PEDOT composite electrodes exhibited good electrical properties and high durability for repeated washing process. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

동시-공증발 기상 중합을 이용한 전도성 PEDOT-PSMA 박막 제조

( Kerguelen Mae Nodora ),임진형 ( Jin-heong Yim ) 한국공업화학회 2018 공업화학 Vol.29 No.3

서로 다른 중합 메카니즘(산화 커플링 중합 및 라디칼 중합)을 가지는 둘 이상의 단량체를 동시에 공-증발 기상 중합(SC-VPP)을 하여 유기-유기 전도성 복합 박막을 제조하는 새로운 접근법을 보고한다. 본 연구에서는 SC-VPP 공정을 통해 poly(3,4-ethylenedioxythiophene)(PEDOT)와 poly(styrene-co-maleic anhydride)(PSMA)로 구성된 PEDOT-PSMA 복합박막을 제조하였다. 유기-유기 전도성 복합체 박막의 제조는 FT-IR 및 ¹H-NMR 분석을 통해 확인되었다. 전자주사현미경을 통한 표면 형태학 분석으로 PEDOT-PSMA 박막이 PEDOT 박막보다 좀 더 거친 표면을 보였다. 이것은 소수성 특성을 가지는 PEDOT과 친수성 특성기를 가지는 PSMA와의 좋지 않은 상용성 때문이라고 생각된다. 따라서 PEDOT-PSMA는 PEDOT보다 낮은 전기 전도도를 나타내었지만 약염기인 2-ethyl-4-methyl imidazole을 첨가하면 크게 개선되었다. PEDOT-PSMA의 접촉각은 PEDOT의 경우 62°에 비해 약 50°로 친수성이 증가하였고, 이는, PSMA가 가지는 카르보닐기에 의한 것이라 판단된다. 제안된 SC-VPP 기반 유기-유기 하이브리드 박막 제조 경로를 통하여 다양한 고분자 전도성 박막의 표면 특성(친수특성, 기계적 강도, 광학특성 및 표면 거칠기) 등을 제어할 수 있다고 판단한다. A new approach for the fabrication of organic-organic conducting composite thin films using simultaneous co-vaporization vapor phase polymerization (SC-VPP) of two or more monomers that have different polymerization mechanisms (i.e., oxida-tion- coupling polymerization and radical polymerization) was reported for the first time. In this study, a PEDOT-PSMA com-posite thin film consisting of poly(3,4-ethylenedioxythiophene)(PEDOT) and poly(styrene-co-maleic anhydride)(PSMA) was prepared by SC-VPP process. The preparation of organic-organic conductive composite thin films was confirmed through FT-IR and ¹H-NMR analyses. The surface morphology analysis showed that the surface of PEDOT-PSMA thin film was rougher than that of PEDOT thin film. Therefore, PEDOT-PSMA exhibited lower electrical conductivity than that of PEDOT. But the conductivity can be improved by adding 2-ethyl-4-methyl imidazole as a weak base. The contact angle of PEDOT-PSMA was about 50°, as compared to 62° for PEDOT. The demonstrated methodology for preparing an organic-or-ganic conductive hybrid thin film is expected to be useful for adjusting intrinsic conductive polymer (ICP)’s surface properties such as mechanical, optical, and roughness properties.

Improved Stability of Interfacial Energy-Level Alignment in Inverted Planar Perovskite Solar Cells

Im, Soeun,Kim, Wanjung,Cho, Wonseok,Shin, Dongguen,Chun, Do Hyung,Rhee, Ryan,Kim, Jung Kyu,Yi, Yeonjin,Park, Jong Hyeok,Kim, Jung Hyun American Chemical Society 2018 ACS APPLIED MATERIALS & INTERFACES Vol.10 No.22

<P>Even though poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) has been commonly used as a hole extraction layer (HEL) for p-i-n perovskite solar cells (PSCs), the cells’ photovoltaic performance deteriorates because of the low and unstable work functions (WFs) of PEDOT:PSS versus those of a perovskite layer. To overcome this drawback, we synthesized a copolymer (P(SS-<I>co</I>-TFPMA)) ionomer consisting of PSS and tetrafluoropropylmethacrylate (TFPMA) as an alternative to conventional PEDOT:PSS. The PEDOT:P(SS-<I>co</I>-TFPMA) copolymer solution and its film exhibited excellent homogeneity and high phase stability compared with a physical mixture of TFPMA with PEDOT:PSS solution. During spin coating, a self-organized conducting PEDOT:P(SS-<I>co</I>-TFPMA) HEL evolved and the topmost PEDOT:P(SS-<I>co</I>-TFPMA) film showed a hydrophobic surface with a higher WF compared to that of the pristine PEDOT:PSS film because of its chemically bonded electron-withdrawing fluorinated functional groups. Interestingly, the WF of the conventional PEDOT:PSS film dramatically deteriorated after being coated with a perovskite layer, whereas the PEDOT:P(SS-<I>co</I>-TFPMA) film represented a relatively small influence. Because of the superior energy-level alignment between the HEL and a perovskite layer even after the contact, the open-circuit voltage, short-circuit current, and fill factor of the inverted planar p-i-n PSCs (IP-PSCs) with PEDOT:P(SS-<I>co</I>-TFPMA) were improved from 0.92 to 0.98 V, 18.96 to 19.66 mA/cm<SUP>2</SUP>, and 78.96 to 82.43%, respectively, resulting in a 15% improvement in the power conversion efficiency vs that of IP-PSCs with conventional PEDOT:PSS. Moreover, the IP-PSCs with PEDOT:P(SS-<I>co</I>-TFPMA) layer showed not only improved photovoltaic performance but also enhanced device stability due to hydrophobic surface of PEDOT:P(SS-<I>co</I>-TFPMA) film.</P> [FIG OMISSION]</BR>

Interface engineering of G-PEDOT: PSS hole transport layer via interlayer chemical functionalization for enhanced efficiency of large-area hybrid solar cells and their charge transport investigation

Hilal, Muhammad,Han, Jeong In Elsevier 2018 SOLAR ENERGY -PHOENIX ARIZONA THEN NEW YORK- Vol.174 No.-

<P><B>Abstract</B></P> <P>In this study, in order to minimize the recombination current of free charge carriers in a large-area organic-inorganic hybrid solar cell (O-IHSCs), we improved the electrical conductivity of a graphene (G) and poly(3,4-ethylenedioxy thiophene)–poly(styrenesulfonate) (G-PEDOT:PSS) hole transport layer (HTL) by introducing various concentrations of synthesized graphene (G) into poly(3,4-ethylene dioxythiophene):poly(styrenesulfonate) (PEDOT:PSS). The electrical conductivity of G-PEDOT:PSS was enhanced to 932781.17 S m<SUP>−1</SUP> via the addition of 2 mg/mL of G to PEDOT:PSS. The O-IHSCs fabricated with the highly conductive G-PEDOT:PSS composite as HTL enhanced the power conversion efficiency (PCE) to 3.90%, a 70% increase compared to O-IHSCs fabricated with pristine PEDOT:PSS HTL. However, the accumulation of G at a higher concentration (2.5 mg/mL) degrades the performance of the solar cell, which generated further defects or film aggregation, interfering with the fast transport of free charge carriers toward their respective electrodes. The G-PEDOT:PSS composite contained various types of functionalization via interfacial reaction between the G and PEDOT:PSS based on Raman and X-ray photoelectron spectroscopy studies. These chemical functionalizations provide an additional mechanism of charge transport via bridges enhancing the carrier mobility and suppression of recombination of free charge carriers, resulting in significant improvement in photovoltaic performance of the O-IHSCs.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Simple fabrication technique approached for hybrid solar cells (O-IHSCs). </LI> <LI> The interface of G-PEDOT:PSS composite HTL chemically functionalized. </LI> <LI> It enhances the electrical conductivity of G-PEDOT:PSS ~ 1 million (S/m). </LI> <LI> G-PEDOT:PSS composite HTL based O-IHSCs exhibit 3.90% of PCE. </LI> <LI> This Si/P3HT:PCBM/G-PEDOT:PSS interfaces may be recommended for commercial O-IHSCs. </LI> </UL> </P>

동시-기상중합법을 이용한 Poly(3,4-ethylenedioxythophene)(PEDOT)-TiO₂

고영수(Young Soo Ko),한용현(Yong Hyeon Han),임진형(Jin Heong Yim) 한국고분자학회 2014 폴리머 Vol.38 No.4

반도체 특성을 가지는 금속산화물이 포함된 poly(3,4-ethylenedioxytionphene) (PEDOT)-TiO2 하이브리드 전도성 박막을 동시-기상중합법을 이용하여 성공적으로 제조하였다. PEDOT- TiO2 박막은 PEDOT 박막에 비하여 내스크래치성, 연필경도와 같은 기계적 물성과 전기/광학적 특성을 향상시킬 수 있었다. 동시-기상중합법으로 제조된 하이브리드 박막은 FTS 산화제에 의한 졸-젤 반응으로 물리화학적으로 안정한 가교구조의 TiO2 층이 균일하게 형성되어 PEDOT 박막자체의 전기/광학적 손실을 수반하지 않고 기계적 물성을 높일 수 있었다. 동시-기상중합을 통하여 제조된 하이브리드 박막은 PEDOT박막에 비하여 평탄한 표면구조를 가졌으며, 이로 인하여 상대적으로 높은 전기 전도도를 가진다. PEDOT-TiO2 hybrid conductive film including semiconductive metal oxide was successfully prepared via simultaneous vapor phase polymerization (VPP). The mechanical properties such as pencil hardness and anti-scratch property as well optoelectrical properties of PEDOT-TiO2 hybrid thin film could be improved as compared with pris-tine PEDOT thin film. Physicochemically stable crosslinked TiO2 layer derived from a sol-gel process by FTS was gen-erated in the PEDOT thin film layer by simultaneous VPP, resulting in improving mechanical properties of the hybrid thin films without any deterioration of their original optoelectrical properties. PEDOT-TiO2 hybrid thin film showed better electrical conductivity as compared with PEDOT film. It might be due to the fact surface morphology of hybrid thin film prepared by simultaneous VPP showed smoother than of pristine PEDOT thin film.

분자간 거리가 PEDOT의 광전자 특성에 미치는 영향

이승현,김경호,강현구,박지상 한국물리학회 2021 새물리 Vol.71 No.12

We investigated both the atomic and the electronic structures of poly(3,4-ethylene dioxythiophene) (PEDOT) by performing first-principles calculations and the optical properties by performing experiments. In our first-principles calculation, the use of different exchange-correlation potentials and van der Waals corrections optimize the distance between molecules differently, directly influencing the calculated band gap of PEDOT. In order to experimentally obtain the optical band gap, high-quality semiconducting PEDOT thin films were prepared using vapor-phase polymerization and chemical reduction process. The bandgap of PEDOT was then extracted from the absorption edge in the measured extinction spectrum. Direct comparison between the measured and calculated bandgap shows that the hybrid density functional theory improves the agreement with the experiments. 본 연구에서는 poly(3,4-ethylenedioxythiophene) (PEDOT) 의 원자 구조와 전자 구조를 여러제일원리 계산 방법론을 이용하여 계산하고, 광학적 특성을 실험을 통해 확인하였다. 제일 원리 계산결과 교환-상관 퍼텐셜과 판데르발스 상호작용 기술 방식에 따라 분자 사이의 거리가 다르게 기술되며, 결과적으로 계산된 PEDOT의 밴드갭에 직접적인 영향을 미친다는 것을 발견했다. 광학적 밴드갭을실험적으로 얻기 위해, 고품질 반도체 PEDOT 박막을 기상 중합방법과 화학적 환원 공정을 통해 제작했다. PEDOT의 밴드갭은 측정된 흡광 스펙트럼의 흡수 끝 파장으로부터 추출되었다. 측정된 밴드갭과 계산된 밴드갭의 직접 비교를 통해 하이브리드 밀도범함수 이론 계산이 실험값과 더 일치하는 밴드갭을 기술하는것을 확인할 수 있었다.

Highly Conductive, Flexible, and Robust Silver Nanowire-Embedded Carboxymethyl Cellulose/Poly(3,4-Ethylenedioxythiophene):Poly(Styrenesulfonate) Composite Films for Wearable Heaters and On-Skin Sensors

Joo Won Han,Ajeng Prameswati,Siti Aisyah Nurmaulia Entifar,Jung Ha Kim,Anky Fitrian Wibowo,Jihyun Park,Jonghee Lee,Soyeon Kim,Dong Chan Lim,Myoung‑Woon Moon,Min‑Seok Kim,Yong Hyun Kim 대한금속·재료학회 2022 ELECTRONIC MATERIALS LETTERS Vol.18 No.6

Highly conductive, flexible, and durable silver nanowire (AgNW)-embedded carboxymethyl cellulose (CMC)/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) (s-CMC/PEDOT:PSS) composite films were investigated forapplication in wearable heaters and on-skin sensors. The electrical conductivities of the CMC/PEDOT:PSS composites wereoptimized by controlling the PEDOT:PSS weight ratio in CMC, and the sheet resistance decreased significantly from 6828(CMC:PEDOT:PSS = 1:5) to 83 Ω/sq (CMC:PEDOT:PSS = 1:17). Furthermore, AgNW networks were embedded onto thesurface of the CMC/PEDOT:PSS films to further enhance their conductivity. The introduction of AgNW networks resultedin a significant decrease in the sheet resistance of the composites from 81 to 7 Ω/sq. In addition, the s-CMC/PEDOT:PSScomposite film exhibited high mechanical stability in repeated bending tests. The uniformly distributed AgNWs inside thecomposites enhanced the electrical contact between the conducting PEDOT:PSS domains in the CMC matrix. Based on thehighly conductive, flexible, and robust s-CMC/PEDOT:PSS composite films, high-performance wearable heating devicesand on-skin sensors were fabricated. The wearable heater achieves a high temperature of 159.5 ℃ with uniform temperaturedistribution. Furthermore, on-skin sensors with s-CMC/PEDOT:PSS composites were conformably integrated on human skinwhich successfully detected various human motions, including finger bending, wrist bending, skin touch, ankle motions, andwalking in real-time. The sensors exhibit high sensing performance with high sensitivity, conformability, superior mechanicalrobustness, and low power consumption. The high-performance s-CMC/PEDOT:PSS composite film could be a promisingflexible and conductive composite material with new opportunities in next-generation electronics.

Preparation and electrochemical performances of NiS with PEDOT:PSS chrysanthemum petal like nanostructure for high performance supercapacitors

S., Srinivasa Rao,Punnoose, Dinah,Bae, Jin-Ho,Durga, Ikkurthi Kanaka,Thulasi-Varma, Chebrolu Venkata,Naresh, Bandari,Subramanian, Archana,Raman, Vivekanandan,Kim, Hee-Je Elsevier 2017 ELECTROCHIMICA ACTA Vol.254 No.-

<P><B>Abstract</B></P> <P>This paper reports the facile synthesis of a novel architectural of NiS/PEDOT:PSS with DEG, where the complementary features of the three components (well-defined NiS black pepper like nanoparticles on nickel foam, an ultrathin layers of poly (3,4-ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT:PSS), and diethylene glycol (DEG)) are deposited sequentially to a single entity to fabricate a high-performance electrode for supercapacitor applications. Owing to the high electrical conductivity of the well-defined NiS nanoparticles, in which the conductivity, and good chemical and electrochemical stability is enhanced further by the PEDOT:PSS and DEG thin layers, the as-fabricated NiS/PEDOT:PSS with a DEG chrysanthemum petal-like nanostructure exhibits good rate capability, excellent cycling stability, and high specific capacitance. The PEDOT:PSS with DEG offers extra conductive paths for each layer on NiS, yielding a lower internal resistance and charge-transfer resistance than that of the NiS/PEDOT:PSS without DEG. As a result, the NiS/PEDOT:PSS with the DEG electrode shows a tremendous pseudocapacitance of 750.64Fg<SUP>−1</SUP> at 1.11Ag<SUP>−1</SUP>, along with a high energy density of 24.52Whkg<SUP>−1</SUP> at a power density of 138.88Wkg<SUP>−1</SUP> and good cycling stability, suggesting that it is a promising candidate for energy storage. The unique performance of NiS/PEDOT:PSS with a DEG benefits from its unique chrysanthemum petal-like nanostructure, which could offer faster ion and electron transfer ability, greater reaction surface area and good structural stability.</P> <P><B>Highlights</B></P> <P> <UL> <LI> NiS/PEDOT:PSS with DEG chrysanthemum petals were prepared using a facile bar-coating method. </LI> <LI> NiS/PEDOT:PSS with DEG showed greater electrochemical properties. </LI> <LI> Improved penetration of electrolyte ions into the electrode was observed by the attachment PEDOT:PSS on NiS. </LI> <LI> The electrode exhibited a high specific capacitance of 750.64Fg<SUP>−1</SUP> at 1.11Ag<SUP>−1</SUP>. </LI> <LI> The nanocomposite displayed excellent cycling stability. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>