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.

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>

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>

Effect of Residual Sodium Ion on Electrical Properties and Colloidal Stability of PEDOT:PSS nanoparticles

조한결,김영노,이진근,조원석,김중현 한국공업화학회 2018 한국공업화학회 연구논문 초록집 Vol.2018 No.0

PEDOT:PSS is promising conducting polymer in terms of its application to transparent and flexible electronic device. Generally, PEDOT:PSS is polymerized by oxidative polymerization using sodium persulfate and iron(III)sulfate as oxidants. After polymerization, especially sodium ions remain in aqueous state. It cause PEDOT:PSS solution to decrease electrical properties and colloidal stability. In this study, we reduced sodium ions to about 20ppm by exchange reaction. Also, we figure out the influence of sodium ions on PEDOT:PSS nanoparticles which related to interaction between PEDOT and PSS chain. The conformational changes between PEDOT and PSS chain are investigated with XPS, UPS, Raman spectroscopy and AFM. Further, the effect of sodium ions on colloidal stability of PEDOT:PSS is analyzed by viscosity change. And we finally investigate that unremoved sodium ions in PEDOT:PSS solution have a considerable influence on its electrical property and colloidal stability of PEDOT:PSS.

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.

Study on stability of PEDOT:PSS films according to acidity of PEDOT:PSS solution using imidazole-based materials

조아라,김세열,김중현 한국공업화학회 2015 한국공업화학회 연구논문 초록집 Vol.2015 No.0

Among the conducting polymer, PEDOT:PSS has received a great attention due to the commercial potential such as solution processability, good mechanical ductility and high optical transparency. For these reasons, the PEDOT:PSS films are applicable to a wide range of applications. However, it is not suitable for direct application without any post-treatments because the sheet resistance increases when the PEDOT: PSS films are exposed to the atmosphere. In this study, Imidazole was added to PEDOT:PSS solution as antioxidant in order to overcome these disadvantages. We investigated the electrical stability of the PEDOT: PSS films according to the acidity. Fabricated PEDOT:PSS Films were characterized through a variety of analysis, including UV-Vis-NIR optical absorbance spectrometry, XPS, and Raman spectroscopy. Improved stability and optical properties of PEDOT:PSS films are suitable for a numerous application.

Flexible p-type PEDOT:PSS/a-Si:H hybrid thin film solar cells with boron-doped interlayer

Lee, Yoo Jeong,Yeon, Changbong,Lim, Jung Wook,Yun, Sun Jin Elsevier 2018 SOLAR ENERGY -PHOENIX ARIZONA THEN NEW YORK- Vol.163 No.-

<P><B>Abstract</B></P> <P>We reported highly flexible a-Si:H thin film solar cells with p-type poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) window. We firstly adopted the substrate-type cell structure on 75 μm-thick polyimide (PI) film unlike earlier studies in which the superstrate-type cell structures were utilized and the deformation of PEDOT:PSS was inevitably caused by subsequent deposition processes. We clearly demonstrated that the performance of the hybrid a-Si:H thin film solar cells with the substrate-type structure was superior to that of the superstrate-type cells. A highly boron-doped interlayer (IL) of 5 nm thickness was introduced at the hetero-interface between the p-type PEDOT:PSS and intrinsic a-Si:H to enhance built-in potential and form a homogeneous p/i-junction in the cell, which led to further improvement in the cell performance. The efficiencies of the cells with the PEDOT:PSS/IL window on glass and PI substrates were 7.40% and 6.52%, respectively, which were considerably higher than that of the cell with a conventional p-type microcrystalline (μc-) Si:H window. Also, the degradation of the cell with PEDOT:PSS window by bending was much smaller than the cell with p-type μc-Si:H window, particularly at bending radius < 10 mm. The present work demonstrates that PEDOT:PSS with a proper interfacial layer is a promising p-type window for substrate-type a-Si:H thin film solar cells and also for enhancing the flexibility of inorganic light absorbing materials-based solar cells on flexible film substrates.</P> <P><B>Highlights</B></P> <P> <UL> <LI> p-Type PEDOT:PSS windows were used for flexible a-Si:H thin film PV cells. </LI> <LI> PEDOT:PSS should be free from a damage caused by subsequent deposition process. </LI> <LI> Surfactant addition and H<SUB>2</SUB>-treatment improve the adhesion of PEDOT:PSS on a-Si:H. </LI> <LI> Insertion of highly B-doped Si leads to further improvement in cell performances. </LI> <LI> Cell with PEDOT:PSS showed higher flexibility than cell with p-type μc-Si:H particularly at bending radius < 10 mm. </LI> </UL> </P>

Enhanced functionalities of DNA thin films by facile conjugation with conducting polymers

Prathamesh Chopade,Sreekantha Reddy Dugasani,Sohee Jeong,Jun-Ho Jeong,Sung Ha Park 한국물리학회 2020 Current Applied Physics Vol.20 No.1

In this study, we discuss a method to embed PEDOT:PSS into DNA with a designated concentration of PEDOT:PSS and construction of PEDOT:PSS-embedded DNA thin films. In order to shed light on the interaction between PEDOT:PSS and DNA, optical spectroscopy measurements were performed. DNA-PEDOT:PSS thin films showed a broad absorption band around 800 nm which was associated with PEDOT:PSS. The electrical properties of DNA-PEDOT:PSS thin films were assessed. A significant enhancement in current for DNA-PEDOT:PSS thin films DNA was observed which agreed with the decrement in band gap of DNA-PEDOT:PSS thin films. For the energy storage capability and dielectric constant of DNA-PEDOT:PSS thin films, capacitance measurements were conducted. Frequency-dependent capacitance indicated enhancement in the capacitance and dielectric constant by electric polarization of PEDOT:PSS in a DNA thin film. Our approach may assist in development of various biosensors and electronic devices with specific functionalities based on biomaterials and conducting polymer complexes.

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>

Tuning the Work Function of Printed Polymer Electrodes by Introducing a Fluorinated Polymer To Enhance the Operational Stability in Bottom-Contact Organic Field-Effect Transistors

Kim, Se Hyun,Kim, Jiye,Nam, Sooji,Lee, Hwa Sung,Lee, Seung Woo,Jang, Jaeyoung American Chemical Society 2017 ACS APPLIED MATERIALS & INTERFACES Vol.9 No.14

<P>Poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) is a promising electrode material for organic electronic devices due to its high conductivity, good mechanical flexibility, and feasibility of easy patterning with various printing methods. The work function of PEDOT:PSS needs to be increased for efficient hole injection, and the addition of a fluorine-containing material has been reported to increase the work function of PEDOT:PSS. However, it remains a challenge to print PEDOT:PSS electrodes while simultaneously tuning their work functions. Here, we report work function tunable PEDOT:PSS/Nafion source/drain electrodes formed by electrohydrodynamic printing technique with PEDOT:PSS/Nafion mixture solutions for highly stable bottom contact organic field-effect transistors (OFETs). The surface properties and work function of the printed electrode can be controlled by varying the Nafion ratio, due to the vertical phase separation of the PEDOT:PSS/ Nafion. The PEDOT:PSS/Nafion electrodes exhibit a low hole injection barrier, which leads to efficient charge carrier injection from the electrode to the semiconductor. As a result, pentacene-based OFETs with PEDOT:PSS/Nafion electrodes show increased charge carrier mobilities of 0.39 cm(2)/(V.s) compared to those of devices with neat PEDOT:PSS electrodes (0.021 cm(2)/(V.s)). Moreover, the gate-bias stress stability of the OFETs is remarkably improved by employing PEDOT:PSS/Nafion electrodes, as demonstrated by a reduction of the threshold voltage shift from -1.84 V to -0.28 V.</P>