Article
Chemistry, Physical
Kyunghan Ahn, Ga Hye Kim, Se-Jun Kim, Jihyun Kim, Gi-Seong Ryu, Paul Lee, Byungki Ryu, Jung Young Cho, Yong-Hoon Kim, Joohoon Kang, Hyungjun Kim, Yong-Young Noh, Myung-Gil Kim
Summary: This study reports the synthesis of highly conductive transparent p-type sulfur-doped CuI (CuI:S) thin film using a liquid-iodination method with a thiol additive. The CuI:S film exhibits a remarkably high electrical conductivity and optical transmittance, achieving a record-high figure of merit (FOM) value. The CuI:S electrode is successfully utilized in transparent electronic devices.
CHEMISTRY OF MATERIALS
(2022)
Article
Chemistry, Physical
Salih Ozbay, Nursev Erdogan, Fuat Erden, Merve Ekmekcioglu, Busra Rakop, Mehtap Ozdemir, Gulnur Aygun, Lutfi Ozyuzer
Summary: ITO, ZTO, AZO, and Ag are commonly used in multilayer thin films of transparent conducting oxide (TCO)/metal/TCO electrodes, with critical knowledge of surface free energy (SFE) being important for designing desirable TCO-based sandwich structures. Contact angle measurements of different liquids were used to evaluate the wettability properties of TCO, Ag interlayer, and TCO/Ag/TCO. The results showed that the SFE components varied depending on the TCO type, the total SFE values of TCO/Ag/TCO films were lower than TCO films, and AZO/Ag adhesion was stronger than other TCO/Ag structures.
APPLIED SURFACE SCIENCE
(2021)
Review
Biochemistry & Molecular Biology
Hong Yong Sohn, Arun Murali
Summary: This article reviews and summarizes recent work in this laboratory on the synthesis of advanced transparent conducting oxide nanopowders using plasma. The process involves selecting suitable precursors, injecting them into a non-transferred thermal plasma, vaporizing them, and forming nanosized oxide particles through vapor-phase reactions. The thermal plasma process shows great potential as an efficient technique for synthesizing oxide nanopowders.
Article
Chemistry, Physical
Ke-Ding Li, Po-Wen Chen, Kao-Shuo Chang
Summary: In this study, two different transparent conducting oxides (TCOs), ITO and IZTO, were compared for their transparent conducting films fabrication processes at different temperatures. It was found that IZTO-based ECDs exhibited higher optical transmittance modulation compared to ITO-based ECDs. The investigation also included electrochromic WO3 films deposited on both ITO and IZTO-based ECDs using vacuum cathodic arc plasma (CAP).
Article
Materials Science, Multidisciplinary
Bo-Yen Lin, Tzu-Chan Lin, Tien-Lung Chiu, Jhih-Hao Lin, Chia-Hsun Chen, Jiun-Haw Lee, Mao-Kuo Wei
Summary: By using a corrugated indium zinc oxide thin film and attaching a hemispheric macrolens, the external quantum efficiency of a blue phosphorescent organic light-emitting device was significantly increased, resulting in a 1.83 times higher efficiency compared to a planar device.
ORGANIC ELECTRONICS
(2021)
Article
Chemistry, Multidisciplinary
Ji Ae Kang, Junseop Lim, Jun Yeob Lee
Summary: Spirobifluorene-based materials with electron transport units show improved performance as electron transport layers, reducing device driving voltage, enhancing quantum efficiency, and increasing the lifetime of green phosphorescent organic light-emitting diodes.
MATERIALS CHEMISTRY FRONTIERS
(2022)
Article
Chemistry, Multidisciplinary
Chengzhao Luo, Zhishuai Zheng, Yanhui Ding, Zhenwei Ren, Hengfei Shi, Huifeng Ji, Xin Zhou, Yu Chen
Summary: In this study, a strategy of electrostatic force-induced deposition (EF-ID) is proposed to improve the pixel accuracy and transmittance of quantum dot light-emitting diodes (QLEDs). By introducing alternating polyethyleneimine (PEI) and fluorosilane patterns, the resolution and transparency of QD patterns are synergistically improved. High-performance QLEDs with high resolution and efficiency, as well as transparent QLEDs with the highest transmittance, are achieved.
ADVANCED MATERIALS
(2023)
Article
Optics
Hosein Ghobadi, Herman L. Offerhaus, Jose A. Alvarez-Chavez, Monica Morales-Masis, Israel De Leon
Summary: Transparent Conducting Oxides (TCOs) in the Epsilon-Near-Zero (ENZ) spectral region exhibit a large and ultrafast intensity-dependent refractive index, which is highly dependent on material properties and measurement conditions. This study demonstrates that extensive nonlinear optical measurements can be avoided by analyzing the material's linear optical response. By considering thickness-dependent material parameters, the impact on absorption and field intensity enhancement under different measurement conditions can be determined, allowing for optimization of the nonlinear response. Experimental measurements of Indium-Zirconium Oxide (IZrO) thin films with varying thicknesses confirm the agreement between experiment and theory, and show that film thickness and excitation angle can be adjusted simultaneously for optimizing the nonlinear optical response, enabling flexible design of highly nonlinear TCO-based optical devices.
Article
Optics
Qi Zhu, Liang Zhou, Weiqiang Liu, Yingjie Cui, Ruixia Wu, Jiahai Wang, Qingduo Duanmu
Summary: An efficient blue organic electroluminescent device was achieved by optimizing the double light-emitting layers structure, selecting appropriate host materials, and adjusting the doping concentration. The device exhibited good thermal stability and high current efficiency, making it a promising candidate for practical applications in the field of optoelectronics.
OPTICS AND LASER TECHNOLOGY
(2021)
Article
Chemistry, Physical
Anna S. Miroshnichenko, Konstantin Deriabin, Maria Baeva, Fedor M. Kochetkov, Vladimir Neplokh, Vladimir V. Fedorov, Alexey M. Mozharov, Olga Yu Koval, Dmitry Krasnikov, Vlad A. Sharov, Nikita A. Filatov, Dmitry S. Gets, Albert G. Nasibulin, Sergey Makarov, Ivan S. Mukhin, Vadim Yu Kukushkin, Regina M. Islamova
Summary: The combination of transparent and durable silicone rubbers with semiconductor materials has enabled the design of highly flexible LEDs. By developing electrodes based on composite materials and nanowires, a novel platform for fabrication of flexible optoelectronic devices has been proposed.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Optics
Guanhao Liu, Zhiyi Li, Xiaoxiao Hu, Yuanyuan Qin, Chun-Sing Lee, Dongqi Chen, Lingxue Wang, Jianjun Liu, Pengfei Wang, Yong-Jin Pu, Ying Wang
Summary: This study demonstrates highly efficient and stable OLEDs with thicknesses of over 1 mu m and low operating voltages. MoO3/SimCP2 is used as a hole-injection layer and a thick layer of TAPC is used as a hole-transporting layer. A thin layer of HAT-CN is incorporated to suppress electron leakage. The research paves the way for large-area OLED-based displays and lighting with high production yields.
Article
Chemistry, Multidisciplinary
Yong Ha Hwang, Seonil Kwon, Jeong Bin Shin, Hyuncheol Kim, Young Hyun Son, Ho Seung Lee, Byeongju Noh, Minwoo Nam, Kyung Cheol Choi
Summary: A novel fiber-based textile display has been developed to address issues such as high power consumption, limited brightness, and lack of addressability, demonstrating unprecedented optoelectronic performance and the highest CE values. By implementing an independent pixel structure, letter information can be successfully visualized on daily clothes, showing the potential for wearable textile displays in the future.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Engineering, Electrical & Electronic
Takeshi Kamijo, Suzanne de Winter, Pradeep Panditha, Eric Meulenkamp
Summary: The transparent conductive electrode (TCE) is an important component of organic light-emitting diodes (OLEDs). This study explores the use of high-resolution printed metal grids as an alternative to indium tin oxide (ITO). By using a thick doped hole injection layer (HIL), electrical shorts can be prevented and high-quality OLEDs with acceptable leakage current can be achieved. The study also reveals that by using very fine pitch and narrow line width, the luminance of the copper (Cu) grid OLED can potentially match that of an ITO-based OLED.
ACS APPLIED ELECTRONIC MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Jun Cheng, Xi Zhang, Zhuanqing Yang, Gang Xiang
Summary: ITO nanofibers prepared by MPC demonstrate excellent electrical and optical properties, showing great potential for applications in electronics and optics.
Article
Materials Science, Multidisciplinary
Hisaki Tsuneyama, Hisahiro Sasabe, Yu Saito, Taito Noda, Daiki Saito, Junji Kido
Summary: In this study, highly stable and efficient deep-red OLEDs were achieved by using a novel exciplex host system. The optimized device exhibited a lifetime that was 6.6 times longer than state-of-the-art deep-red OLEDs and maintained a high maximum external quantum efficiency at a low operating voltage.
JOURNAL OF MATERIALS CHEMISTRY C
(2022)
Article
Chemistry, Physical
Won-Yong Jin, Manoj Mayaji Ovhal, Hock Beng Lee, Barkha Tyagi, Jae-Wook Kang
Summary: A flexible self-charging photocapacitor was developed to provide sustainable energy for wearable devices. By combining flexible organic solar cells and supercapacitors, the performance of the capacitor was improved, achieving a 3.2V charge in 5 minutes.
ADVANCED ENERGY MATERIALS
(2021)
Article
Energy & Fuels
Hock Beng Lee, Neetesh Kumar, Barkha Tyagi, Keum-Jin Ko, Jae-Wook Kang
Summary: The use of fluorinated aromatic organic spacer cation FPEAI to fine-tune the dimensionality and surface morphology of perovskite films has been demonstrated, leading to the formation of a novel 3D/2D interface in perovskite films and the suppression of charge recombination. PSCs treated with FPEAI show significantly improved efficiency and stability, making them a promising approach for producing high-performance and stable multi-dimensional PSCs.
Article
Chemistry, Applied
Jae Ho Kim, Soon Kyu Hong, Seok-Ju Yoo, Chae Young Woo, Jin Woo Choi, Daseul Lee, Jae-Wook Kang, Hyung Woo Lee, Myungkwan Song
Summary: Carbon materials are utilized as CEs in solid-state fiber-shaped DSSCs to replace expensive noble metals, yielding a high power conversion efficiency of 4% and excellent mechanical properties and stability, making them suitable for flexible wearable electronics and energy textiles in the next generation.
Article
Chemistry, Physical
Neetesh Kumar, Hock Beng Lee, Rishabh Sahani, Barkha Tyagi, Sinyoung Cho, Jong-Soo Lee, Jae-Wook Kang
Summary: Spray-deposited SnO2 films exhibit controllable thickness, granular morphology, high transmittance, and contribute to improved performance and scalability of perovskite solar cells. The high efficiency and storage stability of PSCs based on spray-SnO2 ETL make it a promising candidate for large-scale production in the future.
Article
Materials Science, Multidisciplinary
Ho Kwang Choi, Sukang Bae, Seoung-Ki Lee, Sang Hyun Lee, Kisu Lee, Seok-Young Ko, Jae-Wook Kang, Si-Yeong Yang, Tae-Wook Kim
Summary: This study investigated the effects of internally tailored porous structures using size-controlled copper nanosheets on the electromagnetic interference (EMI) shielding performance. The results showed that the shielding performance increased as the size of the copper nanosheets increased.
MATERIALS SCIENCE AND ENGINEERING B-ADVANCED FUNCTIONAL SOLID-STATE MATERIALS
(2022)
Article
Chemistry, Physical
Barkha Tyagi, Hock Beng Lee, Neetesh Kumar, Won-Yong Jin, Keum-Jin Ko, Manoj Mayaji Ovhal, Rishabh Sahani, Hak-Jun Chung, Jangwon Seo, Jae-Wook Kang
Summary: In this study, a scalable fabrication method for semitransparent perovskite solar cells (ST-PSCs) was demonstrated. The use of a three-dimensional transparent conducting electrode (TCE) with excellent optoelectronic properties as the top contact enabled high power conversion efficiency and ambient thermal stability.
Article
Materials Science, Multidisciplinary
Hong Hee Kim, Soohyung Park, Keum-Jin Ko, Sang-Youp Yim, Jae-Wook Kang, Won Kook Choi
Summary: This study successfully synthesized a non-toxic quasi-type-II ZnO@1-Aminopyrene/TPBi/LiF/Al material and fabricated a highly bright and stable blue-emissive quantum dot LED display. The display exhibits high luminance, narrow emission spectrum, high luminous efficacy, and long lifetime.
ADVANCED OPTICAL MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
S. He, H. B. Lee, N. Kumar, K-J Ko, M. Song, W. Kim, J-W Kang
Summary: This paper introduces a method of using cesium lead halide quantum dots and performing ligand/anion exchange to successfully control the optical properties of quantum dot solid-state films, achieve tunable emission of the full-color spectrum, and fabricate full-color perovskite quantum dot light-emitting diodes using this method.
MATERIALS TODAY CHEMISTRY
(2022)
Article
Chemistry, Physical
Barkha Tyagi, Neetesh Kumar, Hock Beng Lee, Manoj Mayaji Ovhal, Vinayak Vitthal Satale, Asmaa Mohamed, Do-Hyung Kim, Jae-Wook Kang
Summary: In this study, a spray-assisted sequential deposition technique is used for large-area perovskite film fabrication, and the effect of propylene carbonate (PC) solvent additive on the transformation of lead halide into perovskite at room temperature is investigated. The results show that PC-modified perovskite films have a uniform, pinhole-free morphology and exhibit oriented grains. The addition of PC solvent also prolongs the fluorescence lifetime and reduces carrier recombination. The champion perovskite solar cells based on PC-modified perovskite film achieve power conversion efficiencies of 20.5% and 19.3% at active areas of 0.09 cm(2) and 1 cm(2), respectively. Additionally, perovskite solar modules with an area of approximately 13 cm(2) are fabricated, achieving a conversion efficiency of 15.8%. The spray deposition technique, combined with the PC additive, shows great promise for economical and high-output preparation of perovskite solar cells.
Article
Energy & Fuels
Neetesh Kumar, Hock Beng Lee, Barkha Tyagi, Manoj Mayaji Ovhal, Sinyoung Cho, Jong-Soo Lee, Jin-Woo Oh, Jae-Wook Kang
Summary: In recent years, researchers have used spray deposition technology to fabricate tin oxide electron transport layer (ETL) for perovskite solar cells (PSC). However, the power conversion efficiency (PCE) of spray-deposited SnO2 ETL is lower than that of spin-coated SnO2 ETL. This study demonstrates the combined use of spray deposition and genetically engineered M13 bacteriophages to deposit M13-SnO2 biohybrid ETL over large-area substrates, resulting in improved PCE of approximately 22.1% and enhanced stability of the PSCs.
Article
Chemistry, Physical
Manoj Mayaji Ovhal, Hock Beng Lee, Shahd Boud, Keum-Jin Ko, Won-Yong Jin, Neetesh Kumar, Barkha Tyagi, Jae-Wook Kang
Summary: The advancement in stripe/fiber-shaped optoelectronic devices fabrication has boosted the performance of smart textile electronics. ITO-free flexible transparent conductive electrodes (TCEs) are highly desirable for high-performance smart textile electronics. In this study, large-area PEDOT:PSS/Ag-fibers hybrid TCEs (DIW-TCEs) were developed using spin-coating and three-dimensional direct-ink writing (3D-DIW) techniques for flexible organic solar cells (OSCs). The DIW-TCEs exhibited excellent electrical conductivity, optical transmittance, and mechanical flexibility. Stripe-OSCs based on DIW-TCEs achieved high power conversion efficiency. A flexible power module constructed using stripe-OSCs successfully lit up a commercial LED. The DIW-TCEs can serve as an ITO-free alternative for smart textile electronics production.
MATERIALS TODAY ENERGY
(2023)
Article
Chemistry, Physical
Barkha Tyagi, Neetesh Kumar, Hock Beng Lee, Young Min Song, Sinyoung Cho, Jong-Soo Lee, Jae-Wook Kang
Summary: Wide-bandgap perovskite solar cells are crucial as top cells in perovskite-based tandem solar cells. However, poor band alignment with the charge transport layer and unwanted parasitic absorption in the top semitransparent perovskite solar cells limit the power conversion efficiency of tandem solar cells.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Physical
Hai Li, Hock Beng Lee, Jae-Wook Kang, Sooman Lim
Summary: A polymer-nanoparticle-liquid (PNL) ternary composite was designed for piezoelectric nanogenerators (PENGs), which showed improved stress transfer ability and achieved record-high piezoelectric performance. The PNL-PENG also demonstrated potential for shape recognition and represents a milestone in the field of human-machine interaction.
Article
Chemistry, Inorganic & Nuclear
Vinayak Vitthal Satale, Neetesh Kumar, Hock Beng Lee, Manoj Mayaji Ovhal, Sagnik Chowdhury, Barkha Tyagi, Asmaa Mohamed, Jae-Wook Kang
Summary: Developing an efficient electron transport layer (ETL) with low defects, high optical transparency, and charge selectivity is crucial for high-performance perovskite solar cell (PSC) devices. In this study, a low-temperature fabrication method for tin oxide (SnO2) ETLs with a bilayer structure and inkjet-printing of triple-cation perovskite films were demonstrated. The optimized SnO2-bilayer ETL exhibited a nano-granule-textured surface, fewer defects, and a cascade conduction band position with the inkjet-printed perovskite film. The champion PSC device based on the SnO2-bilayer ETL and inkjet-printed perovskite film achieved a remarkable power conversion efficiency (PCE) of approximately 16.9%, significantly higher than the device using conventional SnO2 ETL (PCE approximately 14.8%). The improved photovoltaic performance of the SnO2-bilayer-based device can be attributed to enhanced charge transport and reduced recombination at the ETL/perovskite interface. The presented SnO2-bilayer ETL and inkjet-printed perovskite films have great potential for large-scale manufacturing of photovoltaic modules.
INORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Green & Sustainable Science & Technology
Hock Beng Lee, Neetesh Kumar, Sinyoung Cho, Seungyeon Hong, Hyun Hwi Lee, Hyo Jung Kim, Jong-Soo Lee, Jae-Wook Kang
Summary: By using a novel passivator additive called 4-(trifluoromethyl)benzylammonium iodide (CF(3)BZAI), the morphology and crystallinity of perovskite films can be enhanced, and defects can be significantly reduced. Interestingly, the use of CF(3)BZAI does not lead to the formation of a low-dimensional perovskite phase.
ADVANCED ENERGY AND SUSTAINABILITY RESEARCH
(2023)
