fnctId=bbs,fnctNo=4885 총 186 건이 등록되었습니다. 게시물 검색 제목 작성자 공통(상단고정) 공지 게시글 게시글 리스트 (186) S. He, W. Zhou, S.-H. Baek, K.-J. Ko, J. Luo, B.-J. Lee, H.B. Lee*, J.-H. Lee* and J.-W. Kang* "Enhanced Light Outcoupling of Perovskite Quantum Dot Light-Emitting Diodes: Significance of the Refractive Index Control of the Hole Transport Layers and the Thickness of Indium Tin Oxide" in submission (2024.06) 작성자 강재욱 조회수 15 첨부파일 0 등록일 2024.06.03 ABSTRACT Perovskite quantum dot light-emitting diodes (PeQLEDs) are frequently considered as the ideal organic light-emitting diodes (OLEDs) alternatives. However, the efficiency of PeQLEDs remains inferior to OLEDs because their charge carrier transport and intrinsic light outcoupling efficiency ( out) are not optimized. To improve the charge injection and out of PeQLEDs, synergistic hole transport layer (HTL) engineering and substrate engineering are demonstrated herein. The HTL bilayer (modified PEDOT:PSS and PVK) exhibits a lower refractive index, reduced surface roughness, and fewer trap densities at the HTL-QDs interface. For substrate engineering, the ideal thickness of ITO to realize optimal out of PeQLEDs is identified by both optical simulations and experimental verification. With the incorporation of HTL bilayer and 70-nm-thick ITO, the PeQLEDs achieved an external quantum efficiency of 17.96% at a luminance of 1763 cd m-2 and 15.19% at 8300 cd m-2 without using any external outcoupling structure, indicating a low efficiency roll-off. (185) J.H. Kim, G. Kim, S.-J. Kim, Y.B. Kim, J.-W. Kang, J.W. Choi,* J.-W. Oh* and M. Song* "Novel Strategy towards Efficiency Enhancement of Flexible Optoelectronic Devices with Engineered M13 Bacteriophage" in press Small Structure (2024.05) 작성자 강재욱 조회수 14 첨부파일 0 등록일 2024.06.03 AbstractPlasmonic nanostructures, which exhibit notable localized surface plasmon resonance (LSPR) properties, are a promising approach for improving the efficiency of fiber-shaped dye-sensitized solar cells (FDSSCs) and flexible organic light-emitting diodes (FOLEDs). Herein, novel plasmonic nanostructure is successfully synthesized via the self-densification of gold nanoparticles (Au NPs) onto a genetically engineered M13 bacteriophage template. The synthesized Au NP-M13 bio-nanostructure show extraordinary gap-plasmon effects and significantly enhanced LSPR properties compared to randomly dispersed Au NPs for both solid-state FDSSCs (SS-FDSSCs) and FOLEDs. Briefly, a power conversion efficiency (PCE) increment of 40.7% is recorded for the Au metallic NPs-anchored M13 bacteriophage (Au NPs-M13) enhanced SS-FDSSCs; whereas an external quantum efficiency (EQE) increment of 47.2% is achieved for the Au NPs-M13 enhanced FOLEDs.https://doi.org/10.1002/sstr.202400007 (184) K.-J. Ko*, H.W. Cho, H.B. Lee, P.J. Jesuraj, J.-W. Kang*, S.Y. Ryu* "Indium-free, highly flexible semi-transparent organic light-emitting diodes featuring MoO3/Au/MoO3 multilayer anode and cathode" Organic Electronics, 128, 107022 (2024) 작성자 강재욱 조회수 36 첨부파일 0 등록일 2024.03.06 Highlights Flexible transparent OLEDs (Tr-OLEDs) with inverted architecture demonstrated. MoO3/Au/MoO3 electrodes employed as top/bottom electrodes with 76% transmittance. The efficiencies flexible Tr-OLEDs are similar to that of conventional ITO devices. High mechanical robustness and stable performance attained with 1 mm bending radius. MAM electrode can replace ITO for large-area flexible optoelectronic applications.AbstractOrganic light-emitting diodes (OLEDs) typically exhibit a high contrast ratio, wide viewing angles, and low power consumption, enabling their widespread use in display and lighting applications. More recently, transparent OLEDs (Tr-OLEDs) that offer design versatility, seamless integration with the environment, and a minimized obstruction of the view have been developed and applied in various fields including display devices. Here, we report the fabrication of solution-processed, flexible Tr-OLEDs with an inverted device architecture. To ensure the high transparency of the Tr-OLEDs, oxide/metal/oxide (OMO)-structured electrodes, namely MoO3/Au/MoO3 (MAM), were used as both the transparent cathode and anode. The MAM electrodes exhibited a transmittance of 76% at a wavelength of 550 nm and a low sheet resistance of 15 ohm/sq. Moreover, the as-fabricated flexible Tr-OLEDs exhibited efficiency comparable to that of the bottom-emitting OLEDs with MAM and silver electrodes, thus proving the excellent charge carrier-to-light conversion within the device. Additionally, the flexible Tr-OLEDs were mechanically robust and exhibited excellent performance retention even up to a bending radius of 1 mm. Our findings suggest that MAM electrodes can be replace indium-doped tin oxide (ITO) for applications in large-area flexible transparent display and lighting.https://doi.org/10.1016/j.orgel.2024.107022 (183) V.V. Satale, H.B. Lee, B. Tyagi, M.M. Ovhal, S. Chowdhury, A. Mohamed, D.-H. Kim and J.-W. Kang* "Ink engineering using 1,3-dimethyl-2-imidazolidinone solvent for efficient inkjet-printed triple-cationic perovskite solar cells" Chemical Engineering Journal, 493, 152541 (2024) 작성자 강재욱 조회수 81 첨부파일 0 등록일 2024.02.18 Highlights Perovskite films were fabricated using a scalable inkjet printing (IJP) technique. 1,3-dimethyl-2-imidazolidinone (DMI) high boiling solvent used in perovskite ink. DMI-based IJP perovskite has a uniform, smoother film with large grains surface. IJP perovskite has a more suitable energy band alignment with SnO2 and Spiro-OMeTAD. The champion device achieved a PCE of 17.5 % and module PCE of 11.4 % (A = 12.3 cm2).AbstractInk engineering increases the quality and uniformity of large-scale perovskite films for efficient inkjet-printed perovskite solar cells (IJP-PSCs). The absorber layer in PSCs must be pinhole- and crack-free, highly uniform, with minimum defects, and have better optoelectronic properties, to improve PSC device performance. Herein, a different strategy, such as solvents with high boiling points (BPs), is used to modify the perovskite inks to obtain uniform and better-quality IJP-perovskite films. The perovskite film prepared with a 1,3-dimethyl-2-imidazolidinone (DMI) solvent is highly uniform ( 96 %), thicker, with a smoother surface, and contains bigger grains than -butyrolactone (GBL) based IJP-perovskites. The DMI solvent-based IJP-PSC device shows a greater than 17.5 % power conversion efficiency (PCE), which is much higher than that possible with GBL-based devices (PCE 13.8 %). The better performance of the IJP-PSC device is mainly due to the film s uniformity, large grains, and well-formed structures, which reduce the occurrence of specific chemical reactions within the perovskite material. The presented ink engineering strategy to develop highly uniform IJP perovskite films has the potential to be applied to perovskite solar modules.Graphical abstractA high boiling point solvent is used to engineer the perovskite ink for efficient, stable inkjet-printed perovskite solar cell (IJP-PSC) devices. The 1,3-dimethyl-2-imidazolidinone (DMI) solvent-based ink exhibited a highly uniform and smoother film, creating larger grains that resulted in efficient charge transfer to electron or hole transport layers. The DMI solvent-based IJP-PSC device showed an impressive power conversion efficiency of 17.50%, with better stability proving its potential for the scalable fabrication of inkjet-printed PSCs.https://doi.org/10.1016/j.cej.2024.152541 (182) H.B. Lee, A. Mohamed, N. Kumar, N.H.Z. Karimy, V.V. Satale, B. Tyagi, D.-H. Kim and J.-W. Kang* "Low-Cost, Scalable Fabrication of Multi-Dimensional Perovskite Solar Cells and Modules Assisted by Mechanical Scribing" in submission (2024.6) 작성자 강재욱 조회수 44 첨부파일 0 등록일 2024.02.18 Abstract formamidinium lead triiodide (FAPbI3) absorber are often hindered by defects at the surface and grain boundaries of the perovskite. To address this, we demonstrate the use of pyrrolidinium iodide for the in-situ formation of an energetically aligned one-dimensional (1D) pyrrolidinium lead triiodide (PyPbI3) capping layer over the 3D FAbI3 perovskite. The thermodynamically stable PyPbI3 perovskitoids, formed through cation exchange reactions, effectively reduces surface and grain boundary defects in the FAPbI3 perovskite. In addition to improved phase stability, the resulting 1D/3D perovskite film forms a cascade energy band alignment with the other functional layers in PSCs, enabling a barrier-free interfacial charge transport. With a maximum power conversion efficiency (PCE) of ~23.1% and ~20.7% at active areas of 0.09 and 1.05 cm2, respectively, the 1D/3D PSCs demonstrate excellent performance and scalability. Leveraging this improved scalability, we have successfully developed a mechanically-scribed 1D/3D perovskite mini-module with an unprecedentedly high PCE of ~20.6% and a total power output of ~270 mW at an active area of ~13.0 cm2. The 1D/3D multi-dimensional perovskite film developed herein holds great promise for producing low-cost, high-performance perovskite photovoltaics at both the cell and module levels. (181) K. Yadav, M. M. Ovhal, S. Parmar, N. Gaikwad, S. Datar, J.-W. Kang, and T. U. Patro* “ NiCo2O4 Nanoneedle-Coated 3D Reticulated Vitreous Porous Carbon Foam for High-Performance All-Solid-State Supercapacitors” ACS Appl. Nano Mater. 7, 2312–2324 (2024) 작성자 강재욱 조회수 32 첨부파일 0 등록일 2024.02.15 A binder-free, electrically conducting nickel cobalt oxide (NiCo2O4)-reticulated vitreous carbon (RVC) foam (NiCo2O4@RVC) electrode was prepared by template carbonization of open-cell polyurethane foam followed by the hydrothermal growth of NiCo2O4 nanoneedles, leading to the formation of a hierarchical porous electrode. The growth of NiCo2O4 nanoneedles (length and diameter) on RVC foam was found to depend on hydrothermal coating time, which varied between 6 and 12 h. However, optimally grown NiCo2O4 nanoneedles for 8 h on an RVC foam with an average diameter of 77( 9) nm and length of 2 m exhibited the lowest charge-transfer resistance, resulting in the areal capacitance (Ca) of 2.45 F/cm2 at a scan rate of 5 mV/s. A symmetric supercapacitor (SC) device exhibited a maximum Ca of 1.22 F/cm2 at a current density of 1 mA/cm2 and an energy density of 2.51 W h/kg at a power density of 30 W/kg. The SCs showed a capacitance retention of 97% after 10,000 galvanostatic charge/discharge (GCD) cycles, apparently due to a highly stable NiCo2O4 structure on the RVC network structure, which was ascertained by various characterization techniques after the GCD cycles. Further, the SC module, comprising three devices in series, successfully lights up an LED, demonstrating the energy storage capability of these electrodes in real applications. Owing to its excellent electrochemical performance, the NiCo2O4@RVC electrode offers a low-cost and efficient alternative material in energy storage applications.Received4 December 2023Published inissue 26 January 2024https://doi.org/10.1021/acsanm.3c05812 (180) M.M. Ovhal, H.B. Lee, N. Kumar, J.-W. Oh and J.-W. Kang* “ Filamentous Virus-Templated Nickel Hydroxide Nanoplates as Novel Electrochemical Pseudocapacitor Materials” Polymer Korea. 48, 234-241 (2024). 작성자 강재욱 조회수 30 첨부파일 0 등록일 2024.02.15 Pseudocapacitive metal hydroxide nanostructures are promising active electrode materials for supercapacitor applications. Here, we demonstrate the in-situ growth of nickel hydroxide (Ni(OH)2) nanostructures on filamentous M13 bacteriophage template. The M13-Ni(OH)2 bio-nanostructure exhibits a fibrous morphology and a preferential growth orientation along the (001) crystal plane. Interestingly, the M13-Ni(OH)2 electrode demonstrates superior electrochemical properties. The areal capacitance (Ca) of M13-Ni(OH)2 and Ni(OH)2 electrodes was 18 mF/cm2 and 14 mF/cm2, respectively, indicating a 28% increase. The improved electrochemical performance is due to increased surface roughness, enhanced charge adsorption/desorption sites, and reduced charge transfer resistance. This also contributed to an 18% increase in cyclic stability compared to the Ni(OH)2 electrode analogue. Overall, this work successfully shows the use of a bio-template to control the growth of novel metal-oxide nanostructures for energy storage applications.Received December 18, 2023;http://journal.polymer-korea.or.kr/journal/archive/view/4442 (179) M.M. Ovhal, H.B. Lee, V.V. Satale, B. Tyagi, N. Kumar, S. Chowdhury and J.-W. Kang* “One-meter-long, All-3D-printed Supercapacitor Fibers based on Structurally Engineered Electrode for Wearable Energy Storage” Adv. Energy Mater. 14, 2303053 (2024) 작성자 강재욱 조회수 57 첨부파일 0 등록일 2023.12.26 AbstractFiber-shaped energy storage devices have great potential for use as an intelligent power source for futuristic wearable technology. To produce high-performance fiber-shaped energy storage devices, a thin fiber material with a high energy density, shape adaptability, and longevity is critical. Herein, 3D fiber-shaped supercapacitors (SCs) comprising MXene-PEDOT:PSS active electrodes made using the 3D-direct-ink-writing (DIW) technique are demonstrated. Embedding a silver (Ag) current collector in the active electrode facilitated faster charge transport in the fiber-shaped 3D-SCs, enabling them to create a unique 3D-electrode structure that solves the thickness and length problem of electrode-dependent capacitance in fiber-shaped devices. At one-meter long, the fully-printed fiber-shaped 3D-SC exhibits a low charge transfer resistance that leads to the high areal capacitance of 1.062 F cm 2 and gravimetric capacitance of 185.9 F g 1, with a high areal energy density of 94.41 Wh cm 2 at a power density of 1,142 W cm 2. The fiber-shaped 3D-SCs also exhibit excellent electrochemical and mechanical stability at different temperatures in air and water. With their unique electrode structure and uninterrupted power supply, these R2R 3D-DIW printed fiber-shaped SCs can boost the development of innovative textile technology.https://doi.org/10.1002/aenm.202303053 (178) Hai Li, Hock Beng Lee, Jae-Wook Kang, Sooman Lim* “Three-dimensional polymer-nanoparticle-liquid ternary composite for ultrahigh augmentation of piezoelectric nanogenerators” Nano Energy, 113, 108576 (2023). 작성자 강재욱 조회수 106 첨부파일 0 등록일 2023.06.28 Highlights A novel polymer-nanoparticle-liquid ternary composite based piezoelectric nanogenerator is developed. PFOES liquid nanodroplets, BTO NPs, and PVDF polymer have collectively formed a stable composite with a 3D scaffold. The ternary composite exhibits a remarkably improved stress transfer ability and enhanced energy harvesting output. This PNL-PENG device can function as a tactile perception tool.AbstractThe development of flexible nanogenerators that can convert passively generated environmental energy into electricity is crucial for sustainable energy generation. Herein, we rationally designed a polymer-nanoparticle-liquid (PNL) ternary composite, comprising polydopamine-modified barium titanate nanoparticles (PDA-BTO NPs) doped polyvinylidene fluoride (PVDF), and 1H,1H,2H,2H-perfluorodecyltriethoxysilane (PFOES) liquid nanodroplets, for application in piezoelectric nanogenerators (PENGs). The inter-discrete PFOES nanodroplets enabled the formation of a three-dimensional (3D) scaffold matrix in the ternary composite, which is highly beneficial for the stress transfer of PENGs. Finite-element analysis revealed that the ternary composite had a remarkably improved stress transfer ability due to the incorporation of highly deformable PFOES liquid nanodroplets, which increased the net stress exerted on PDA-BTO NPs and the PVDF matrix. The PNL composite-based PENG (PNL-PENG) device exhibited an enhanced piezoelectric performance, achieving an output voltage, current, and power density of 102 V, 10 A, and 70 W/cm2, respectively, which are record-high results compared to those achieved by binary composite-based PENGs. Moreover, the PNL-PENG also demonstrated tremendous potential to function as a highly sensitive tactile perception tool for shape recognition. The concept of PNL-PENG devices represents a milestone in the domain of human-machine interaction, taking a significant step toward the advancement of flexible and wearable electronics. https://www.sciencedirect.com/science/article/pii/S2211285523004135Published 2023. 08. 01 (177) W. Yang, G. Park, A. Liu, H.B. Lee, J.-W. Kang*, H. Zhu* and Y.-Y. Noh* "Fluorinated Organic A-Cation Enabling High-Performance Hysteresis-Free 2D/3D Hybrid Tin Perovskite Transistor" Adv. Funct. Mater. 33, 2303309 (2023) 작성자 강재욱 조회수 128 첨부파일 0 등록일 2023.05.02 Two-dimensional (2D) tin-based perovskites have gained considerable attention for use in diverse optoelectronic applications, such as solar cells, lasers, and thin-film transistors (TFTs), owing to their good stability and optoelectronic properties. However, their intrinsic charge-transport properties are limited and the insulating bulky organic ligands hinder the achievement of high-mobility electronics. Blending three-dimensional (3D) counterparts into 2D perovskites to form 2D/3D hybrid structures is a synergistic approach that combines the high mobility and stability of 3D and 2D perovskites, respectively. In this study, a reliable p-channel 2D/3D tin-based hybrid perovskite TFTs comprising 3D formamidinium tin iodide (FASnI3) and 2D fluorinated 4-fluoro-phenethylammonium tin iodide ((4-FPEA)2SnI4) are reported. The optimized FPEA-incorporated TFTs show a high hole mobility of 12 cm2 V-1 s-1, an on/off current ratio of over 108, and a subthreshold swing of 0.09 V dec-1 with negligible hysteresis. This excellent p-type characteristic is compatible with n-type metal-oxide TFT for constructing complementary electronics. Two procedures of antisolvent engineering and device patterning are further proposed to address the key concern of low performance reproducibility of perovskite TFTs. This study provides an alternative A-cation engineering method for achieving high-performance and reliable tin-halide perovskite electronics.https://doi.org/10.1002/adfm.202303309Publish : September 5, 2023 (176) V.V. Satale, N. Kumar, H.B. Lee, M.M. Ovhal, S. Chowdhury, B. Tyagi, A. Mohamed, and J.-W. Kang* "Spray-Assisted Deposition of SnO2 Electron Transport Bilayer for Efficient Inkjet-Printed Perovskite Solar Cells" Inorganic Chemistry Frontier. 10, 3558–3567 (2023) 작성자 강재욱 조회수 119 첨부파일 0 등록일 2023.04.10 Developing an efficient electron transport layer (ETL) through structural modification is essential to produce high-performance perovskite solar cell (PSC) devices. Specifically, the ETL should exhibit low defects, high optical transparency, and charge selectivity for ideal electron transport. Herein, we demonstrate (i) the low-temperature fabrication of tin oxide (SnO2) ETLs with a bilayer structure, and (ii) inkjet-printing of triple-cation perovskite film. Through the combined use of spin-coating and spray deposition, the optimized SnO2-bilayer ETL shows a nano-granule-textured surface, noticeably lesser defects, and cascade conduction band position with the inkjet-printed (IJP) perovskite. The champion IJP PSC device, based on the SnO2-bilayer ETL recorded an outstanding power conversion efficiency (PCE) of ~16.9%, which is significantly higher than the device based on the conventional SnO2 ETL (PCE ~14.8%). The improved photovoltaic performance of the SnO2-bilayer-based PSC arises mainly from more efficient charge transport and suppressed recombination at the ETL/perovskite interface. The SnO2-bilayer ETL and IJP-perovskite films demonstrated herein can be potentially used for large-scale manufacturing of PSC modules.Submission: 2023.03.31Publicaion: 2023. 06. 21DOIhttps://doi.org/10.1039/D3QI00599B (175) S. He, H.B. Lee, K.-J. Ko, N. Kumar, J.-H. Jang, S.-O. Cho, M. Song, W. Zhou, B.-J. Lee, J.-H. Lee* and J.-W. Kang* "Optical Engineering of FAPbBr3 Nanocrystals via Conjugated Ligands for Light-Outcoupling Enhancement in Perovskite Light-Emitting Diodes" Adv. Opt. Mater. 11, 2300486 (2023) 작성자 강재욱 조회수 144 첨부파일 0 등록일 2023.02.28 Formamidinium lead bromide (FAPbBr3) nanocrystals (NCs) that exhibit ultra-pure green emission are the most promising candidates for future displays. Despite the rapid development of light-emitting diodes (LEDs) based on perovskite NCs (PeNCs), there is limited research detailing their intrinsic light outcoupling. Herein, we propose the use of a short-chain fluoroaromatic ligand, 4-fluoro-phenethylammonium bromide (FPEABr) via a facile spin-casting method to fine-tune the refractive index (n) and horizontal dipole ratio values of the perovskite emitter layer and simultaneously suppress the defects formed during film deposition. After FPEABr ligand exchange, the FAPbBr3 NCs films exhibite a refractive index n significantly lower (by about 0.4) than bulk (2D/quasi 2D or 3D) perovskite films and show an enhanced value of 77%. Therefore, we successfully produce ultra-pure green PeLEDs with a maximum current efficiency of ~ 50 cd A-1, a maximum luminance of 21304 cd m-2, and a peak external quantum efficiency of 11.33% at a high luminance of 2804 cd m-2, approaching the theoretical value of 11.90% given the structure, photoluminance quantum yield, and horizontal dipole ratio. https://doi.org/10.1002/adom.202300486Cover Image : https://onlinelibrary.wiley.com/doi/10.1002/adom.202370066 (174) B. Tyagi, N. Kumar, H.B. Lee, M.M. Ovhal, V.V. Satale, A. Mohamed, D.-H. Kim and J.-W. Kang* “Development of high efficiency, spray-coated perovskite solar cells and modules using additive-engineered porous PbI2 films” Small Method,8, 2300237 (2024) 작성자 강재욱 조회수 123 첨부파일 0 등록일 2023.02.28 Small MethodsResearch ArticleDevelopment of High Efficiency, Spray-Coated Perovskite Solar Cells and Modules Using Additive-Engineered Porous PbI2 FilmsBarkha Tyagi, Neetesh Kumar, Hock Beng Lee, Manoj Mayaji Ovhal, Vinayak Vitthal Satale, Asmaa Mohamed, Do-Hyung Kim, Jae-Wook KangFirst published: 25 May 2023 https://doi.org/10.1002/smtd.202300237Citations: 2AbstractThe development of anti-solvent free, scalable, and printable perovskite film is crucial to realizing the low-cost roll-to-roll development of perovskite solar cells (PSCs). Herein, large-area perovskite film fabrication is explored using a spray-assisted sequential deposition technique. How propylene carbonate (PC) solvent additive affects the transformation of lead halide (PbI2) into perovskite at room temperature is investigated. The result shows that PC-modified perovskite films exhibit a uniform, pinhole-free morphology with oriented grains compared with pristine perovskite films. The PC-modified perovskite film also has a prolonged fluorescence lifetime that indicates lower carrier recombination. The champion PSC devices based on PC-modified perovskite film realize a power conversion efficiency (PCE) of 20.5% and 19.3% at an active area (A) of 0.09 cm2 and 1 cm2, respectively. The fabricated PSCs are stable and demonstrate 85% PCE retention following 60 days of exposure to ambient conditions. Furthermore, perovskite solar modules (A 13 cm2) that yield a PCE of 15.8% are fabricated. These results are among the best reported for the state-of-art spray-coated PSCs. Spray deposition coupled with a PC additive is highly promising for economical and high-output preparation of PSCs.- Submission (2023.2.24). https://doi.org/10.1002/smtd.202300237 (173) N. Kumar, H.B. Lee, B. Tyagi, M.M. Ovhal, S. Cho, J.-S. Lee, J.-W. Oh, J.-W. Kang* “Spray deposited, virus-templated SnO2 mesoporous electron transport layer boosting the performance of perovskite solar cells” Solar RRL, 7, 2300065 (2023) 작성자 강재욱 조회수 195 첨부파일 0 등록일 2022.11.14 In recent years, researchers have developed spray deposition technology to fabricate tin oxide (SnO2) electron transport layer (ETL) with the aim of manufacturing high-efficiency, large-area perovskite solar cell (PSC). However, the power conversion efficiency (PCE) of PSC based on sprayed SnO2 ETL remains inferior to that of the spin-coated SnO2 ETL. Herein, we demonstrate the combined use of spray deposition and genetically-engineered M13 bacteriophages to fabricate M13-SnO2 biohybrid ETL for PSC application. The spray-deposited M13-SnO2 ETLs exhibited mesoporous morphologies with 85% transmittance in UV-vis region. Though the use of M13-SnO2 ETL, the sequential-deposited PSCs achieved a maximum PCE of ~22.1%. The improved performance of the PSC is attributable to the mesoporous morphology of M13-SnO2 ETL that facilitated the phase conversion of PbI2 into perovskite. When sprayed on large area (~62 cm2) substrates, the M13-SnO2 based PSCs displayed a highly consistent PCE, demonstrating the excellent scalability of spraying process. Furthermore, M13-SnO2-based PSCs exhibited higher ambient stability compared to the SnO2-based PSCs.- Submission (2023.1.30). https://doi.org/10.1002/solr.202300065 (172) B. Tyagi, N. Kumar, H.B. Lee, Y.M. Song, S. Cho, J. -S. Lee, J.-W. Kang* “Compact-Porous Hole-Transport-Layer for Highly Efficient Near-Infrared Region Transparent Perovskite Solar Cells for Tandem Applications” J. Alloys Compounds, 960, 170970 (2023) . 작성자 강재욱 조회수 151 첨부파일 0 등록일 2022.11.14 Highlights ● The cp-NiOx films were consecutively fabricated using spin-coating and spray-coating techniques.● The cp-NiOx/perovskite interface possesses lower buried defects.● The cp-NiOx films have mesoporous surface morphology and excellent surface properties for perovskite film formation.● Wide-bandgap perovskite solar cell consisting cp-NiOx HTL yielded PCE of 15.95 % and NIR transmittance ( 92 %).● 4T perovskite/silicon tandem cells based on the cp-NiOx HTL yielded a PCE of 26.0 % with superior stability.AbstractWide-bandgap perovskites solar cells (PSCs) are vital as top cells in perovskite-based tandem solar cells (TSCs). However, poor band alignment with the charge transport layer and unwanted parasitic absorption in the top semitransparent-PSC (ST-PSC) are major factors limiting the power conversion efficiency (PCE) of TSCs. Herein, we present a compact-porous nickel oxide (cp-NiOx) hole-transport layer (HTL) sequentially fabricated using a sol-gel suspension and colloidal suspension of highly crystalline NiOx. The cp-NiOx film exhibited enhanced transparency, mesoporous surface morphology, and better energy band alignment with a 1.68 eV perovskite film for fabricating highly near-infrared transparent ( 92 % (@800 1200 nm)) ST-PSCs. The best cell achieved a PCE of 15.9 %. In addition, a four-terminal perovskite/silicon TSC based on the cp-NiOx HTL achieved an outstanding PCE of 26.0 %. The tailored energy band structure and reduced parasitic absorption in the near-infrared region of the ST-PSCs based on the cp-NiOx HTL enabled fabrication of highly efficient inverted ST-PSCs for perovskite/silicon TSCs.https://www.sciencedirect.com/science/article/pii/S0925838823022739- Submission (2022. 9. 20)- Revision (2023. 5. 10)- Published (2023.10. 15) (171) M.M. Ovhal, H.B. Lee, S. Boud, K.-J. Ko, W.-Y. Jin, N. Kumar, B. Tyagi, J.-W. Kang* “Flexible, stripe-patterned organic solar cells and modules based on multilayer-printed Ag fibers for smart textile applications” Materials Today Energy, 34, 101289 (2023) 작성자 강재욱 조회수 109 첨부파일 0 등록일 2022.11.14 Rapid advancement in the fabrication technologies of stripe/fiber-shaped optoelectronic devices has driven the performance of smart textile electronics to a new height. In the development of high-performance smart textile electronics, ITO-free flexible transparent conductive electrodes (TCEs) are particularly desirable because they offer superior flexibility and lower manufacturing cost than the brittle ITO-based counterparts. Herein, we innovatively combine spin-coating and 3D direct-ink writing (3D-DIW) techniques to develop large-area (5 5 cm2) PEDOT:PSS/Ag-fibers hybrid TCEs (denoted as DIW-TCEs) for application in flexible organic solar cells (OSCs). Through a multilayer printing strategy, high aspect-ratio Ag-fibers are successfully deposited on top of the planar PEDOT:PSS film. The resulting DIW-TCEs, when fully embedded in a colorless polyimide substrate, exhibit excellent electrical conductivity (sheet resistance ~ 4 Ω/□), superior optical transmittance, and mechanical flexibility. One-dimensional stripe-patterned OSCs (stripe-OSCs) based on the DIW-TCE achieved a power conversion efficiency (PCE) of 9.3% and 8.2% at an active area of 0.11 cm2 and 0.31 cm2, respectively. For real-life application, a flexible power module was constructed using eight stripe-OSCs. When attached on textile, the module successfully lit up a commercial LED upon photocharging. The unique DIW-TCE fabricated herein can be the ITO-free alternative for the production of smart textile electronics.June 2023https://doi.org/10.1016/j.mtener.2023.101289 (170) H.B. Lee, N. Kumar, S. Cho, S. Hong, H.H. Lee, H.J. Kim, J.-S. Lee, J.-W. Kang* “Intercalation of Ammonium Cationic Ligands Enabled Grain Surface Passivation in Sequential-Deposited Perovskite Solar Cells” Adv. Energy & Sustainability Res. 4, 2200128 (2023). 작성자 강재욱 조회수 81 첨부파일 0 등록일 2022.11.14 Solution-processed formamidinium lead iodide (FAPbI3) perovskite typically contains a high number of ionic defects that are intrinsically formed during film formation. To reduce the defects, which undermine the performance and stability of FAPbI3 films, post-synthetic surface passivation treatment is widely practiced. However, the practicality of the surface passivation approach is limited by the poor coverage and incomplete adsorption of passivators into the defective sites. Unprecedentedly, we demonstrate the use of 4-(trifluoromethyl)benzylammonium iodide (CF3BZAI) as a novel passivator additive for sequentially-deposited perovskite films. Due to its unique molecular structure and CF3 moiety, CF3BZAI is expected to have enhanced adsorption with defect sites during the film formation. Owing to grain surface passivation, the CF3BZAI-intercalated FAPbI3 (target) film has enhanced morphology and crystallinity as well as significantly fewer defects than the normal FAPbI3 film. Interestingly, the intercalation of CF3BZAI passivators does not lead to the formation of a low-dimensional perovskite phase in FAPbI3 films. The best perovskite solar cell (PSC) device based on the target film achieved a maximum efficiency of ~22.4%, which is much higher than the efficiency (~20.7%) of the normal device. CF3BZAI-assisted grain surface passivation is a facile yet effective strategy to enhance the performance and stability of FAPbI3-based PSCs.January 2023https://doi.org/10.1002/aesr.202200128 (169) H.B. Lee, R. Sahani, V. Devaraj, N. Kumar, B. Tyagi, J.-W. Oh, J.-W. Kang* “Complex Additive-Assisted Crystal Growth and Phase Stabilization of α-FAPbI3 Film for Highly Efficient, Air-Stable Perovskite Photovoltaics” Adv. Mater. Interface 10, 2201658 (2023). 작성자 강재욱 조회수 133 첨부파일 0 등록일 2022.11.14 Solution-processed formamidinium lead iodide (FAPbI3) perovskite is entropically metastable, and it exhibits condition-induced crystal polymorphism. Under an ambient atmosphere, the photoactive black -FAPbI3 converts easily to photoinactive yellow -FAPbI3. This phase degradation is further accelerated upon exposure to high temperature/humidity, directly threatening the performance and stability of perovskite solar cells (PSCs). Herein, CsI-PbI2:DMSO complex is introduced as a phase stabilizer to modulate the crystallization of -FAPbI3 perovskite from -FAPbI3 precursor and simultaneously, serve as a defect passivator to suppress trap states formation. Theoretical simulations and experimental results reveal the pivotal role of complex additive in optimizing the energy band alignment and optoelectronic properties of -FAPbI3 perovskite and most importantly, hindering the phase transition. The best PSC device based on the additive-engineered perovskite film achieved an efficiency of ~21.9%, which is ~11 % higher than that of its pristine counterpart (~19.8%). Additionally, the incorporation of CsI-PbI2:DMSO complex remarkably enhances the long-term stability and photostability of the PSCs by inhibiting ion migrations and preserving the -phase in FAPbI3 perovskite. The additive engineering presented herein offers a route to produce FAPbI3-based PSCs with improved performance, stability and reproducibility.January 17, 2023https://doi.org/10.1002/admi.202201658 (168) H.H. Kim, S. Park, K.-J. Ko, S.-Y. Yim, J.-W. Kang, W.K. Choi* “Blue Light Emitting Diodes based on Bright Quasi-Type-II ZnO@1-Aminopyrene Hybrid Quantum Dots with a Long Operation Life” Adv. Opt. Mat. 10, 2200601 (2022). 작성자 강재욱 조회수 94 첨부파일 0 등록일 2022.11.14 Non-toxic heavy metal, low-cost indium-free blue emissive quantum dots (QDs) are critical for the realization of self-emissive electroluminescent quantum dot (ELQD) light-emitting diode (LED) displays. A facile and effective hybridization of ZnO QDs with functionalized polyaromatic hydrocarbons (f-PAHs) to synthesize a very bright and stable blue-light emissive quantum-dot LED (QLED) using non-toxic quasi-type-II ZnO@1-Aminopyrene hybrid QDs is reported. The optimized QLEDs of ITO/PEDOT:PSS/TFB/ZnO@1-Aminopyrene/TPBi/LiF/Al demonstrate very bright deep blue-light electroluminescence of 3379 cd m 2 centered at = 441 nm with a full-width-at-half maximum of 41.7 nm and CIE 1931 color coordinates of 0.17 and 0.09, a luminous efficacy of 3.32 cd A 1, power efficiency of 2.45 lm W 1, external quantum efficiency of 2.35%, and a remarkably long lifetime T50 of 17 830 h at 100 cd m 2. https://onlinelibrary.wiley.com/doi/full/10.1002/adom.202200601 (167) S. He, H.B. Lee, N. Kumar, K.-J. Ko, M. Song, W. Kim, J.-W. Kang* "Realizing Full-color Perovskite Quantum Dots Light-Emitting Diodes via Contemporary Surface Ligand/Anion Engineering" Mat. Today Chem 26, 101012 (2022) 작성자 강재욱 조회수 95 첨부파일 0 등록일 2022.11.14 Unprecedentedly, cesium lead halide (CsPbX3, X = Cl, Br, I) quantum dots (QDs) with tunable spectral emissions and photophysical properties are used as a common emissive material for the fabrication of full-color perovskite QDs light-emitting diodes. An efficient, non-destructive ligand/anion exchange strategy is developed to fine-tune the optical properties of CsPbBr3 QDs solid-state films. Specifically, the surface of the CsPbBr3 QDs films is passivated by phenethylammonium halides, PEAX (X = Cl, Br, I) salts via a facile spin-coating technique, producing PEAX-CsPbBr3 QDs (X = Cl, Br, I) films with tunable (blue/green/red) color emissions that cover the entire visible spectrum. During passivation treatment, the PEAX passivators supply additional halide (Cl, Br, I) anions to fill in the intrinsic Br vacancies, allowing contemporary defect-passivation and emission-tuning effect in the QDs film. More importantly, this surface passivation strategy enables the fabrication of full-color perovskite QDs light-emitting diodes using PEAX-CsPbBr3 QDs as a common emissive film. Highlights CsPbBr3 quantum dots (QDs) are synthesized by typical hot-injection method. CsPbBr3 QDs films are passivated using phenethylammonium halide (PEAX, X = Cl, Br, I) via facile spin-coating technique. PEAX (X = Cl, Br, I) passivation of CsPbBr3 produces PEAX-CsPbBr3 QDs with tunable (blue, green, red) emission. PEAX (X = Cl, Br, I) passivation of CsPbBr3 enables the fabrication of full-color displays. https://www.sciencedirect.com/science/article/abs/pii/S2468519422002415 (166) H.K. Choi, S. Bae, S.-K. Lee, S.H. Lee, K. Lee, S.-Y. Ko, J.-W. Kang, T.-W. Kim* "Tailoring the internal structure of porous copper film via size-controlled copper nanosheets for electromagnetic interference shielding" Mat. Sci. & Eng. B 278, 115611 (2022) 작성자 강재욱 조회수 87 첨부파일 0 등록일 2022.11.14 We studied the effects that internal porous structures tailored using size-controlled copper nanosheets (Cu NSs) had on the electromagnetic interference (EMI) shielding performance of the resulting Cu NS films. Cu NSs were carefully synthesized as two-dimensional (2D) conductive fillers, and their size was controlled by adjusting the concentrations of the shape modifier (iodine), stabilizer (hexadecylamine) and reductant (glucose). Three kinds of Cu NSs had the size of 3.8 m (Max. 10.0 m), 8.9 m (Max. 28.0 m), and 12.2 m (Max. 33.7 m) and used as a conductive filler for shielding film by spray printing. The films had different surface coverages, film thicknesses, and EMI shielding effectiveness (SE) at a fixed loading weight of 0.6 mg/cm2. The smallest to largest Cu NSs exhibited EMI shielding performances of 6.3 dB, 43.6 dB, and 69.7 dB, respectively, so performance was directly proportional to size. Highlights Controlling the internal structure of electromagnetic interference(EMI) shielding film is an important issue in the development of EMI shielding applications. Cu NSs size was controlled by adjusting the concentrations of the shape modifier, stabilizer and reductant. The larger Cu NSs formed a more hierarchical porous internal structure than the smaller ones. EMI shielding performances of the smallest to largest Cu NSs was directly proportional to size. The hierarchical porous structure of the larger Cu NSs provided a longer traveling path for incident electromagnetic waves. https://www.sciencedirect.com/science/article/abs/pii/S0921510722000083 (165) B. Tyagi, H.B. Lee, N. Kumar, W.-Y. Jin, K.-J. Ko, M.M. Ovhal, R. Sahani, H.-J. Jung, J. Seo, J.-W. Kang* “High-performance, large-area semitransparent and tandem perovskite solar cells featuring highly scalable a-ITO/Ag mesh 3D top electrodes” Nano Energy 95, 106978 (2022). 작성자 강재욱 조회수 90 첨부파일 0 등록일 2022.11.14 The photovoltaic performance and scalability potential of a semitransparent perovskite solar cells (ST-PSCs) are primarily determined by the optoelectronic properties of the top transparent conducting electrode (TCE) used. Herein, we demonstrate the scalable fabrication of ST-PSC using a three-dimensional (3D) TCE consisting of (i) a sputtered amorphous indium-tin-oxide (a-ITO) film and (ii) silver (Ag) mesh subelectrodes prepared via a 3D direct-ink writing technique. At an optimized aspect ratio of 0.5, the a-ITO/Ag mesh 3D TCE exhibits a sheet resistance of 1 /□ and a transparency of ~85%. Utilizing the a-ITO/Ag mesh as a top contact, standard (0.07 cm2) and large-area (1.0 cm2) ST-PSCs achieved power conversion efficiencies (PCE) of 16.26% and 15.52%, respectively, with 85% transmittance in the near-infrared region. Moreover, the ST-PSCs displayed superior ambient and thermal stability than the opaque PSCs due to the presence of a-ITO buffer that prevents moisture ingress and ions migration. Using ST-PSC as a top cell, the standard (0.07 cm2) and large-area (1.0 cm2) four-terminal ST-PSC/SiSC tandem cells achieved PCEs of 26.47% and 24.70%, respectively. To the best of our knowledge, our tandem cell showed the minimum efficiency roll-off among all the reported large-area tandem cells, manifesting the scalability potential of our ST-PSCs. Highlights a-ITO/Ag mesh 3D TCE are fabricated using sputtering and 3D printing methods. Optimized a-ITO/Ag mesh 3D TCE show 85% transmittance and 1 /□ sheet resistance. Semitransparent perovskite solar cell (ST-PSCs) achieves ~16.3% efficiency and 85% NIR transparency. ST-PSCs exhibits outstanding ambient stability ( 85% after 2000 h) and operational stability ( 88% after 350 h). 4 T perovskite/silicon tandem cells produced a PCE of 26.47% with excellent scalability. https://www.sciencedirect.com/science/article/abs/pii/S2211285522000635 (164) N. Kumar, H.B. Lee, R. Sahani, B. Tyagi, S. Cho, J.-S. Lee, J.-W. Kang* “Room-Temperature Spray Deposition of Large-area SnO2 Electron Transport Layer for High Performance, Stable FAPbI3-based Perovskite Solar Cells” Small Methods 6, 2101127 (2022). 작성자 강재욱 조회수 80 첨부파일 0 등록일 2022.11.14 The performance and scalability of perovskite solar cells (PSCs) is highly dependent on the morphology and charge selectivity of the electron transport layer (ETL). This work demonstrates a high-speed (1800 mm min 1), room-temperature (25 C 30 C) deposition of large-area (62.5 cm2) tin oxide films using a multi-pass spray deposition technique. The spray-deposited SnO2 (spray-SnO2) films exhibit a controllable thickness, a unique granulate morphology and high transmittance ( 85% at 550 nm). The performance of the PSC based on spray-SnO2 ETL and formamidinium lead iodide (FAPbI3)-based perovskite is highly consistent and reproducible, achieving a maximum efficiency of 20.1% at an active area (A) of 0.096 cm2. Characterization results reveal that the efficiency improvement originates from the granular morphology of spray-SnO2 and high conversion rate of PbI2 in the perovskite. More importantly, spray-SnO2 films are highly scalable and able to reduce the efficiency roll-off that comes with the increase in contact-area between SnO2 and perovskite film. Based on the spray-SnO2 ETL, large-area PSC (A = 1.0 cm2) achieves an efficiency of 18.9%. Furthermore, spray-SnO2 ETL based PSCs also exhibit higher storage stability compared to the spin-SnO2 based PSCs. https://onlinelibrary.wiley.com/doi/abs/10.1002/smtd.202101127 (163) H.B. Lee, N. Kumar, V. Devaraj, K.-J. Ko, S. He, B. Tyagi, J.-W. Oh*, J.-W. Kang* “Trifluoromethyl-group bearing, hydrophobic bulky cations as defect passivators for highly efficient, stable perovskite solar cells” Solar RRL 5, 2000589 (2021). 작성자 강재욱 조회수 54 첨부파일 0 등록일 2022.11.14 Solution-processed perovskite films are rich in surface defects and grain boundaries, which limits their performance and stability in photovoltaic application. Surface passivation using bulky organic cations can effectively reduce the surface defects of a perovskite film without affecting its fundamental properties. Herein, the use of hydrophobic bulky aromatic molecules, namely 4-trifluoromethyl-benzylammonium iodide/bromide (CF3BZA-I/Br), as defect-passivators to heal the surface defects and grain boundaries of perovskite films is introduced. Owing to the presence of the trifluoromethyl (CF3) moieties, CF3BZA-I/Br-passivated perovskite films exhibit a hydrophobic surface with significantly fewer grain boundaries. By suppressing the surface and interfacial imperfections, CF3BZA-Br-treated perovskite solar cells achieve an outstanding power conversion efficiency (PCE) of 20.75%. The PCE improvement originates mainly from the reduction of trap states and nonradiative carrier recombination. The ultrathin hydrophobic barrier layer formed after passivation also shields the perovskite film surface from moisture ingress and environmental degradation, leading to improved stability of the devices. By optimizing the passivation conditions, the bulky CF3BZA-I/Br molecules could be the ideal defect passivators, with versatile applications in a wide variety of perovskite optoelectronics. https://onlinelibrary.wiley.com/doi/abs/10.1002/solr.202100712 (162) M.M. Ovhal, N. Kumar, H.B. Lee, B. Tyagi, K.-J. Ko, S. Boud, J.-W. Kang* “Roll-to-Roll 3D-Printing of Flexible, Transparent, All-Solid-State Supercapacitor” Cell Reports Physical Science 2, 100562 (2021). 작성자 강재욱 조회수 170 첨부파일 0 등록일 2022.11.14 Roll-to-roll (R2R) fabrication of flexible and transparent all-solid-state supercapacitors (FT-ASSCs) is extremely challenging because of the classic trade-off between transparency and capacitance. In this work, we develop fully three-dimensional (3D)-printed, sandwich-type FT-ASSCs comprised of 3D line-patterned carbon black (CB)/Ag/CB electrodes on a transparent dialysis membrane (DM) separator. By tailoring the line pitch of the 3D electrodes, our FT-ASSC is able to achieve more than 80% optical transmittance and significantly higher areal capacitance than an opaque ASSC. More importantly, the performance of 3D-printed FT-ASSCs is unrestricted by the transparency-capacitance trade-off, and they exhibit a superior capacitive figure of merit value compared with state-of-the-art FT-ASSCs reported in the literature. Additionally, our FT-ASSCs demonstrate excellent cyclic stability and mechanical robustness because of the chemical and mechanical stability of the DM separator and effective encapsulation of polyurethane. The single-flow 3D printing technique introduced here can meet the requirements for industrial-scale R2R manufacturing of energy storage devices.Highlights Transmittance of FT-ASSCs increases without sacrificing capacitance FT-ASSCs achieve T550 nm of 80.7% 0.9% and ~172% 3% higher Ca than opaque ASSCs Surface area and charge transfer are in line with the thickness of 3D electrodes Roll-to-roll 3D-printed FT-ASSC modules show excellent flexibility and shape adaptivity https://www.sciencedirect.com/science/article/pii/S2666386421002770?via%3Dihub (161) S. He, N. Kumar, H.B. Lee, K.-J. Ko, Y.-J. Jung, J.I. Kim, S. Bae, J.-H. Lee*, J.-W. Kang* “Tailoring the Refractive Index of CsPbBr3 Quantum Dots via Alkyl Cation-Engineering for Efficient Perovskite Light-Emitting Diodes” Chem. Eng. J. 425, 130678 (2021). 작성자 강재욱 조회수 64 첨부파일 0 등록일 2022.11.14 All inorganic CsPbBr3 perovskite quantum dots (PeQDs) have emerged as great candidates for next-generation perovskite quantum dots light-emitting diodes (PeQLEDs) applications due to their excellent optoelectronic and light-emitting properties. However, the performance of CsPbBr3 based PeQLEDs is hindered by (i) the long-chain, synthetic insulating ligands on PeQDs surfaces and (ii) the inherently high refractive index (n) of the PeQDs that often leads to internal light confinement loss. These major shortcomings are addressed by introducing a short-chain ammonium moiety, namely phenethylammonium bromide (PEABr), via spin-coating to passivate the surface of the PeQDs films. PEABr passivation can effectively annihilate the intrinsic bromide vacancies of PeQDs and simultaneously tune the refractive index of the PeQDs films. The reduced n-mismatch between the emitter and the charge transporting layers suppresses the waveguide loss after PEABr passivation and significantly elevates the external quantum efficiency (EQE) and maximum luminance of the PeQLEDs from ~ 1.0% to ~ 6.85% and ~ 1300 cd m 2 to ~ 13000 cd m 2, respectively. More importantly, the environmental stability of the PeQDs also improves remarkably following PEABr passivation. The alky cation engineering demonstrated herein is a facile yet efficient approach to simultaneously boost the performance and stability of CsPbBr3 PeQDs.Highlights CsPbBr3 PeQDs are passivated using PEABr cations via facile spin-coating methods. PEABr passivation mitigates surface defects and tune the index n of CsPbBr3 PeQDs. PEABr passivation improves the optical coupling and yield high luminescence. The passivated CsPbBr3 PeQDs films deliver improved efficiency and stability. https://www.sciencedirect.com/science/article/abs/pii/S1385894721022646 (160) H.B. Lee, N. Kumar, B. Tyagi, S. He, R. Sahani, J-W Kang* “Bulky Organic Cations Engineered Lead-halide Perovskites: A Review on Dimensionality and Optoelectronic Applications” Mat. Today Energy. 21, 100759 (2021). 작성자 강재욱 조회수 117 첨부파일 0 등록일 2022.11.14 Hybrid lead-halide perovskites are widely used in a variety of optoelectronic applications, including perovskite solar cells (PSCs), perovskite light-emitting diodes (PeLEDs), perovskite photodetectors (PPDs), and scintillators. Recently, it was demonstrated that bulky organic cations (BOCs) can be used as surface passivation agents to fine-tune the dimensionality of lead-halide perovskites, making it possible to tailor their optoelectronic properties and enhance their stability. This special feature has further improved the commercialization potential of perovskite-based optoelectronic devices. In this article, we provide a comprehensive review of the recent progress in low/multidimensional perovskites prepared via BOC treatment and their performance in various optoelectronic devices. We begin by introducing the special features and fundamental properties of lead-halide perovskites with different dimensionalities and the working mechanism of BOC treatments. Thereafter, we separately highlight and discuss the device architecture and performance breakthroughs of BOC-treated perovskites in (i) PSCs, (ii) PeLEDs, and (iii) PPDs and scintillators, emphasizing works published from 2018 till now. For each application, the influence of BOC treatments on device performance and stability is discussed. At the end of this review, we provide our insights on future challenges and commercialization opportunities for BOC-treated perovskites in the field of optoelectronics. https://www.sciencedirect.com/science/article/abs/pii/S2468606921001246 (159) K.-J. Ko, S.-R. Shin, H.B. Lee, E. Jeong, Y.J. Yoo, H.M. Kim, Y. M. Song*, J. Yun*, J.-W. Kang* “Fabrication of an oxide/metal/oxide structured electrode integrated with anti-reflective film to enhance performance in flexible organic light-emitting diodes” Mat. Today Energy. 20, 100704 (2021). 작성자 강재욱 조회수 58 첨부파일 0 등록일 2022.11.14 Flexible organic light-emitting diodes (OLEDs) are used widely in optoelectronic devices, with possible new applications, including foldable/rollable displays. Unique features of flexible OLEDs included high brightness, low power consumption, and flexibility. The performance of a flexible OLED is frequently hindered by refractive index difference between the air and the flexible substrate medium, leading to inefficient light outcoupling. To address this issue, we developed a mechanically robust oxide/metal/oxide (OMO) structured transparent conducting electrode (TCE), integrated with silica nanoparticles based antireflective (AR) film, to improve the light extraction efficiency of flexible OLEDs. The AR-OMO structures were prepared on polyethylene terephthalate substrates using a combination of plasma-enhanced chemical vapor deposition and magnetron sputtering. Our results show that an OLED device based on AR-OMO TCE exhibits higher luminance efficiency (LE) and total external quantum efficiency (EQEtot) than devices based on pristine OMO or an indium tin oxide structure due to the presence of AR film that suppresses waveguided-mode light loss at the air-substrate interface. The champion AR-OMO-based flexible OLED devices achieved an LE of 12.3 cd/A and an EQEtot of 5.0%. The AR-OMO device also demonstrated outstanding mechanical flexibility, retaining 100% of its initial luminance up to a bending radius of 6 mm. https://www.sciencedirect.com/science/article/abs/pii/S2468606921000691 (158) J.-H. Kim, S.K. Hong, S.-J. Yoo, C.Y. Woo, J.W. Choi, D. Lee, J.-W. Kang, H.W. Lee,* M. Song* “Pt-free, cost-effective and efficient counter electrode with carbon nanotube yarn for solid-state fiber dye-sensitized solar cells” Dyes and Pigments. 185, 108855 (2021). 작성자 강재욱 조회수 38 첨부파일 0 등록일 2022.11.14 Fiber-shaped solar cells have attracted significant attention for their potential applications in portable and wearable electronics. Developing highly efficient and stable counter electrodes (CEs) to replace rare and expensive noble metals in dye-sensitized solar cells (DSSCs) is a research challenge. The low cost, excellent activity, and stability of carbon materials make them the most qualified noble-metal-free CEs for the commercialization of photovoltaic devices. In this study, we incorporated a carbon nanotube yarn (CNTY) as a CE for efficient and stable solid-state fiber-shaped DSSCs. After device optimization, the power conversion efficiency with the CNTY fiber-shaped DSSCs was approximately 4.00%, which is comparable to that of devices with platinum electrodes (2.64%). The superior mechanical property and performance stability after repeated bending, cleaning, and high output voltage for in-series connection suggest that the proposed CNTY fiber-shaped DSSCs may find applications as flexible power sources in next-generation flexible/wearable fiber electronics and energy textiles. https://www.sciencedirect.com/science/article/abs/pii/S0143720820315527 (157) W.-J. Jin, M.M. Ovhal, H.B. Lee, B. Tyagi and J.-W. Kang* “Scalable, All-Printed Photocapacitor Fibers and Modules based on Metal-Embedded Flexible Transparent Conductive Electrodes for Self-Charging Wearable Applications” Adv. Energy. Mater. 11, 2003509 (2021). 작성자 강재욱 조회수 68 첨부파일 0 등록일 2022.11.14 The popularity of wearable smart electronic gadgets, such as smartphones, smartwatches, and medical sensors, is inhibited by their limited operation lifetime due to the lack of a sustainable self-charging power supply. This constraint can be overcome by developing a flexible, self-charging photocapacitor that can synchronously harvest and store energy. Here, ultrathin, all-printed, and metal-embedded transparent conducting electrodes (ME-TCEs) are designed for the fabrication of large-area, flexible organic solar cells (F-OSCs) and flexible supercapacitors (F-SCs). Stripe-shaped F-OSCs (SF-OSCs) and F-SCs (SF-SCs) are obtained via slitting the as-fabricated F-OSCs and F-SCs with a surgical scalpel, respectively. The SF-OSCs and SF-SCs fully retain their performance after slitting, achieving a power conversion efficiency of 6.43% and areal capacitance of 52 mF cm 2, respectively. Furthermore, photocapacitor fibers are obtained by vertically stacking one SF-OSC and seven SF-SCs. Each fiber is fully encapsulated using UV-curable resin. When woven into a textile, the photocapacitor module (2 series 4 parallel connections) is able to charge up to a voltage of 3.2 V in 5 min under one-sun illumination. The photoelectric-conversion-and-storage efficiency ( ) of the photocapacitor module is 4.94%. The highly tailorable, mechanically robust photocapacitor demonstrated herein can be a secondary, self-sustainable power supply for futuristic wearable applications. https://onlinelibrary.wiley.com/doi/abs/10.1002/aenm.202003509 처음 17 1 2 3 4 5 6 7 다음 페이지 끝