Hyperfluorescence TM , exhibiting 100% energy-to-light conversion efficiency, a sharp yet brighter emission spectrum, and excellent CIE coordinate coverage, is the ultimate 4th generation OLED technology. With our unique approach to material design and device optimization, Kyulux will provide our customers with industry leading fluorophores in all colors. Together, we will deliver unparalleled picture quality and energy efficiency to OLED display market.
{"title":"HyperfluorescenceTM: Recent achievements of Kyulux materials","authors":"Shuo‐Hsien Cheng, A. Endo, T. Hirzel, Yuseok Yang","doi":"10.1117/12.2326825","DOIUrl":"https://doi.org/10.1117/12.2326825","url":null,"abstract":"Hyperfluorescence TM , exhibiting 100% energy-to-light conversion efficiency, a sharp yet brighter emission spectrum, and excellent CIE coordinate coverage, is the ultimate 4th generation OLED technology. With our unique approach to material design and device optimization, Kyulux will provide our customers with industry leading fluorophores in all colors. Together, we will deliver unparalleled picture quality and energy efficiency to OLED display market.","PeriodicalId":158502,"journal":{"name":"Organic Light Emitting Materials and Devices XXII","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123036590","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Electrically-pumped lasing remains an elusive grand challenge for the organic and thin film electronics community. Recently, hybrid organic-inorganic perovskites have emerged as promising gain media for tunable, solution-processed semiconductor lasers, sparking interest in the use of these materials for an eventual diode laser. This talk will focus on recent progress toward this goal, including the demonstration of optically-pumped, continuous-wave lasing from methylammonium lead iodide (MAPbI3) as well as an investigation into the nature of quantum efficiency roll-off in MAPbI3 light emitting diodes operated at current densities exceeding 300 A/cm2.
{"title":"Toward organic-inorganic hybrid perovskite laser diodes (Conference Presentation)","authors":"N. Giebink","doi":"10.1117/12.2318726","DOIUrl":"https://doi.org/10.1117/12.2318726","url":null,"abstract":"Electrically-pumped lasing remains an elusive grand challenge for the organic and thin film electronics community. Recently, hybrid organic-inorganic perovskites have emerged as promising gain media for tunable, solution-processed semiconductor lasers, sparking interest in the use of these materials for an eventual diode laser. This talk will focus on recent progress toward this goal, including the demonstration of optically-pumped, continuous-wave lasing from methylammonium lead iodide (MAPbI3) as well as an investigation into the nature of quantum efficiency roll-off in MAPbI3 light emitting diodes operated at current densities exceeding 300 A/cm2.","PeriodicalId":158502,"journal":{"name":"Organic Light Emitting Materials and Devices XXII","volume":"62 10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122373965","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Organic solid-state lasers (OSSLs) have been widely investigated during the past decades, owing to their amenability to low-cost and low-temperature processing, compatibility with plastic substrates, and broad spectral tunability. A variety of optical resonators have been applied for optically pumped OSSLs, including planar waveguide Fabry-Perot (FP) microcavity, distributed feedback (DFB), whispering-gallery mode (WGM) microring microresonator, and photonic band-gap structures. Nevertheless, electrically driven OSSLs remain still a great challenge, partially because the conflicting requirement between large stimulated emission and high charge carrier mobility narrows the range of organic semiconductor gain materials available for electrically driven OSSLs. Recently, we demonstrated that organic microcrystal with well-defined dimensions and different polymorphisms can serve as microresonators for fundamental investigation of optical confinement effect on laser behaviors, such as nanowire FP and microdisk WGM microlasers. Moreover, organic single crystals are ideal for use as high-mobility materials, because their long-range ordered structures minimize traps and are free from grain boundaries. Therefore, organic microcrystals provide a platform to combine high carrier transport, efficient optical gain, and microresonator together on the way to develop electrically pumped organic lasers. In this talk, I will present our research on the photonic performance of molecular microcrystal microcavities and the latest breakthroughs toward organic microlaser devices. Overall, organic microcrystals bring tunable optical properties based on molecular design, size-dependent light confinement in low-dimensional structures, and various device geometries for nanophotonic integration.
{"title":"Self-assembled organic microcrystal microcavity lasers (Conference Presentation)","authors":"H. Fu, Xue Jin, Zhenyi Yu","doi":"10.1117/12.2319858","DOIUrl":"https://doi.org/10.1117/12.2319858","url":null,"abstract":"Organic solid-state lasers (OSSLs) have been widely investigated during the past decades, owing to their amenability to low-cost and low-temperature processing, compatibility with plastic substrates, and broad spectral tunability. A variety of optical resonators have been applied for optically pumped OSSLs, including planar waveguide Fabry-Perot (FP) microcavity, distributed feedback (DFB), whispering-gallery mode (WGM) microring microresonator, and photonic band-gap structures. Nevertheless, electrically driven OSSLs remain still a great challenge, partially because the conflicting requirement between large stimulated emission and high charge carrier mobility narrows the range of organic semiconductor gain materials available for electrically driven OSSLs. Recently, we demonstrated that organic microcrystal with well-defined dimensions and different polymorphisms can serve as microresonators for fundamental investigation of optical confinement effect on laser behaviors, such as nanowire FP and microdisk WGM microlasers. Moreover, organic single crystals are ideal for use as high-mobility materials, because their long-range ordered structures minimize traps and are free from grain boundaries. Therefore, organic microcrystals provide a platform to combine high carrier transport, efficient optical gain, and microresonator together on the way to develop electrically pumped organic lasers. In this talk, I will present our research on the photonic performance of molecular microcrystal microcavities and the latest breakthroughs toward organic microlaser devices. Overall, organic microcrystals bring tunable optical properties based on molecular design, size-dependent light confinement in low-dimensional structures, and various device geometries for nanophotonic integration.","PeriodicalId":158502,"journal":{"name":"Organic Light Emitting Materials and Devices XXII","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132017239","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We review the progress in modeling of charge transport in disordered organic semiconductors on various length-scales, from atomistic to macroscopic. This includes evaluation of charge transfer rates from first principles, parametrization of coarse-grained lattice and off-lattice models, and solving the master and drift-diffusion equations. Special attention is paid to linking the length-scales and improving the efficiency of the methods. All techniques are illustrated on an amorphous organic semiconductor, DPBIC, a hole conductor and electron blocker used in state of the art organic light emitting diodes. The outlined multiscale scheme can be used to predict OLED properties without fitting parameters, starting from chemical structures of compounds.
{"title":"Modeling of phosphorescent organic light emitting diodes: from molecular to device properties (Conference Presentation)","authors":"D. Andrienko","doi":"10.1117/12.2321081","DOIUrl":"https://doi.org/10.1117/12.2321081","url":null,"abstract":"We review the progress in modeling of charge transport in disordered organic semiconductors on various length-scales, from atomistic to macroscopic. This includes evaluation of charge transfer rates from first principles, parametrization of coarse-grained lattice and off-lattice models, and solving the master and drift-diffusion equations. Special attention is paid to linking the length-scales and improving the efficiency of the methods. All techniques are illustrated on an amorphous organic semiconductor, DPBIC, a hole conductor and electron blocker used in state of the art organic light emitting diodes. The outlined multiscale scheme can be used to predict OLED properties without fitting parameters, starting from chemical structures of compounds.","PeriodicalId":158502,"journal":{"name":"Organic Light Emitting Materials and Devices XXII","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126657864","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
H. Fukagawa, Tsubasa Sasaki, Taku Oono, Takahisa Shimizu
Although flexible optoelectronic devices can be easily fabricated by integrating OLEDs on flexible substrates, this technique suffers from the rapid growth of the non-emitting area due to the oxygen and moisture degradation of reactive electron injection layer materials such as alkali metals. Flexible substrates that can completely block oxygen and moisture are essential for extending the lifetime of flexible devices, but such flexible substrates cannot be easily fabricated. In recent years, inverted OLEDs (iOLEDs) with a bottom cathode have been intensively studied as an ideal structure for realizing air-stable OLEDs. As an alternative to the alkali metals that are commonly used in conventional OLEDs, metal oxides and organic interlayers such as polyethylene imine are employed in most reported iOLEDs. Despite the recent advances in the iOLED technology, the development of interlayers that can prevent the decrease in brightness caused by iOLED operation is lacking. Here, we report the design strategy of an interlayer for the fabrication of efficient and stable iOLEDs. The efficiency and the operational lifetime of the optimized iOLED were comparable to that of the conventional OLED that used the same emitter. Two flexible displays were fabricated to ascertain the feasibility of the application of the interlayer to real devices and the air stability of the iOLED-based devices: one using iOLEDs and the other using conventional OLEDs. The iOLED-based flexible display emits light over 1 year under the simplified encapsulation though the conventional OLED-based flexible display shows almost no luminosity only after 21 days under the same encapsulation.
{"title":"Recent progress in inverted OLEDs: Key materials, air stability, and application to flexible display (Conference Presentation)","authors":"H. Fukagawa, Tsubasa Sasaki, Taku Oono, Takahisa Shimizu","doi":"10.1117/12.2319807","DOIUrl":"https://doi.org/10.1117/12.2319807","url":null,"abstract":"Although flexible optoelectronic devices can be easily fabricated by integrating OLEDs on flexible substrates, this technique suffers from the rapid growth of the non-emitting area due to the oxygen and moisture degradation of reactive electron injection layer materials such as alkali metals. Flexible substrates that can completely block oxygen and moisture are essential for extending the lifetime of flexible devices, but such flexible substrates cannot be easily fabricated. In recent years, inverted OLEDs (iOLEDs) with a bottom cathode have been intensively studied as an ideal structure for realizing air-stable OLEDs. As an alternative to the alkali metals that are commonly used in conventional OLEDs, metal oxides and organic interlayers such as polyethylene imine are employed in most reported iOLEDs. Despite the recent advances in the iOLED technology, the development of interlayers that can prevent the decrease in brightness caused by iOLED operation is lacking. Here, we report the design strategy of an interlayer for the fabrication of efficient and stable iOLEDs. The efficiency and the operational lifetime of the optimized iOLED were comparable to that of the conventional OLED that used the same emitter. Two flexible displays were fabricated to ascertain the feasibility of the application of the interlayer to real devices and the air stability of the iOLED-based devices: one using iOLEDs and the other using conventional OLEDs. The iOLED-based flexible display emits light over 1 year under the simplified encapsulation though the conventional OLED-based flexible display shows almost no luminosity only after 21 days under the same encapsulation.","PeriodicalId":158502,"journal":{"name":"Organic Light Emitting Materials and Devices XXII","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134215495","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Dong Ha Kim, Huan Wang, J. Lim, L. Quan, Ilgeum Lee, E. Sargent
While the field of perovskite-based optoelectronics has mostly been dominated by photovoltaics, light-emitting diodes and transistors, semiconducting properties peculiar to perovskites make them interesting candidates for innovative and disruptive applications in light signal detection. Perovskites combine effective light absorption in the broadband range with good photo-generation yield and high charge carrier mobility, which combination provides promising potential for exploiting sensitive and fast photodetectors that are targeted for image sensing, optical communication, environmental monitoring, or chemical/biological detection. Currently, organic-inorganic hybrid and all-inorganic halide perovskites with controlled morphologies of polycrystalline thin films, nano-particles/wires/sheets, and bulk single crystals have shown key figure-of-merit features in terms of their responsivity, detectivity, noise equivalent power, linear dynamic range, and response speed. The sensing region has been covered from ultraviolet–visible–near infrared (UV–Vis–NIR) to gamma photons, based on two- or three-terminal device architectures. Diverse photoactive materials and devices with superior optoelectronic performances have stimulated attention from researchers in multidisciplinary areas. We offer a comprehensive overview of the recent progress of perovskite-based photodetectors, focusing on versatile compositions, structures, and morphologies of constituent materials, and diverse device architectures toward the superior performance metrics. Combining the advantages of both organic semiconductors (facile solution processability) and inorganic semiconductors (high charge carrier mobility), perovskites are expected to replace commercial silicon for future photodetection applications. The optical and electronic properties of noble metallic nanoparticles can be exploited to enhance the performance of inorganic/organic photodetectors. We integrated a uniformly-distributed layer of Au nanorods (AuNRs) into vertically-structured perovskite photoconductive photodetectors and report, as a result, perovskite-AuNR hybrid photodetectors that exhibit significant photocurrent enhancements. Ultimately it achieves a responsivity of ~320 A/W at a low driving voltage of -1 V. This is an improvement of 60% compared to the responsivity of pristine devices (~200 A/W). The high responsivity and low driving voltage place this device among the highest-performing perovskite-based thin-film photoconductive photodetectors reported. We characterized the stability and linearity of the photoresponse following repeated light/dark cycles. The hybrid device also shows a fast response (with the decay time of ~95 ns) compared to pristine devices (~230 ns). The improvements in photodetection performance are attributed to plasmon-enhanced optical absorption, as well as advances in charge extraction and transport. Metal halide perovskites have rapidly advanced thin film photovoltaic performance;
虽然钙钛矿基光电子学领域主要由光伏、发光二极管和晶体管主导，但钙钛矿特有的半导体特性使其成为光信号检测中创新和颠覆性应用的有趣候选者。钙钛矿结合了宽带范围内有效的光吸收、良好的产光率和高载流子迁移率，这一组合为开发灵敏和快速的光电探测器提供了广阔的潜力，这些探测器可用于图像传感、光通信、环境监测或化学/生物检测。目前，具有多晶薄膜、纳米颗粒/线/片和块状单晶等可控形貌的有机-无机杂化卤化物钙钛矿和全无机卤化物钙钛矿在响应性、探测性、噪声等效功率、线性动态范围和响应速度等方面都表现出了关键的优值特征。基于二端或三端器件架构的传感区域涵盖了从紫外-可见-近红外(UV-Vis-NIR)到伽马光子。各种具有优异光电性能的光活性材料和器件引起了多学科研究者的关注。我们全面概述了钙钛矿基光电探测器的最新进展，重点是组成材料的多种成分、结构和形态，以及不同的器件架构，以实现卓越的性能指标。钙钛矿结合了有机半导体(易于溶液加工)和无机半导体(高载流子迁移率)的优点，有望在未来的光探测应用中取代商业硅。利用贵金属纳米颗粒的光学和电子特性可以提高无机/有机光电探测器的性能。我们将均匀分布的Au纳米棒(aunr)层集成到垂直结构的钙钛矿光导光电探测器中，并报告了钙钛矿- aunr混合光电探测器，结果显示出显着的光电流增强。最终在-1 V的低驱动电压下实现了~320 a /W的响应度。这比原始设备(~ 200a /W)的响应性提高了60%。高响应性和低驱动电压使该器件成为性能最高的钙钛矿基薄膜光导光电探测器之一。我们表征了重复光/暗循环后光响应的稳定性和线性。与原始器件(~230 ns)相比，混合器件也显示出快速的响应(衰减时间为~95 ns)。光探测性能的提高归功于等离子体增强的光吸收，以及电荷提取和传输的进步。金属卤化物钙钛矿迅速提高了薄膜光伏性能;因此，材料的观测不稳定性迫切需要解决。利用密度泛函理论(DFT)，我们证明了低能量的形成，在湿度存在下加剧，解释了钙钛矿分解回其前体的倾向。我们发现，同样使用DFT，在钙钛矿层之间插入苯乙胺引入了定量可观的范德华相互作用;这将增加地层能量，从而提高材料的稳定性。在这里，我们报告了降维(准二维)钙钛矿薄膜，在保持传统三维钙钛矿高性能的同时，表现出更好的稳定性。连续调整的维度，作为评估使用光物理研究，是通过选择stoi-chiometry在材料合成。我们首次在平面全钛矿太阳能电池中实现了无迟滞太阳能转换，获得了15.3%的认证PCE，并大大提高了性能寿命。同样的协议被应用于在不同的设备配置中开发高度稳定和高效的光电探测器。有机金属卤化物钙钛矿具有较大的体晶畴尺寸、罕见的陷阱、优异的迁移率和在室温下自由的载流子，这些特性支持了它们在电荷分离器件中的优异性能。在依赖于正向注入电子和空穴的器件中，如发光二极管(led)，优异的迁移性有助于将非平衡载流子有效地捕获到稀有的非辐射中心。此外，束缚激子的缺乏削弱了期望的辐射重组与不希望的非辐射重组的竞争。在这里，我们还报道了一种钙钛矿混合材料，一种由一系列不同量子尺寸调谐的颗粒组成的材料，它将光激发引导到混合物中最低带隙的光发射器。
{"title":"Optoelectronic hybrid perovskite materials and devices (Conference Presentation)","authors":"Dong Ha Kim, Huan Wang, J. Lim, L. Quan, Ilgeum Lee, E. Sargent","doi":"10.1117/12.2323334","DOIUrl":"https://doi.org/10.1117/12.2323334","url":null,"abstract":"While the field of perovskite-based optoelectronics has mostly been dominated by photovoltaics, light-emitting diodes and transistors, semiconducting properties peculiar to perovskites make them interesting candidates for innovative and disruptive applications in light signal detection. Perovskites combine effective light absorption in the broadband range with good photo-generation yield and high charge carrier mobility, which combination provides promising potential for exploiting sensitive and fast photodetectors that are targeted for image sensing, optical communication, environmental monitoring, or chemical/biological detection. Currently, organic-inorganic hybrid and all-inorganic halide perovskites with controlled morphologies of polycrystalline thin films, nano-particles/wires/sheets, and bulk single crystals have shown key figure-of-merit features in terms of their responsivity, detectivity, noise equivalent power, linear dynamic range, and response speed. The sensing region has been covered from ultraviolet–visible–near infrared (UV–Vis–NIR) to gamma photons, based on two- or three-terminal device architectures. Diverse photoactive materials and devices with superior optoelectronic performances have stimulated attention from researchers in multidisciplinary areas. We offer a comprehensive overview of the recent progress of perovskite-based photodetectors, focusing on versatile compositions, structures, and morphologies of constituent materials, and diverse device architectures toward the superior performance metrics. Combining the advantages of both organic semiconductors (facile solution processability) and inorganic semiconductors (high charge carrier mobility), perovskites are expected to replace commercial silicon for future photodetection applications.\u0000\u0000The optical and electronic properties of noble metallic nanoparticles can be exploited to enhance the performance of inorganic/organic photodetectors. We integrated a uniformly-distributed layer of Au nanorods (AuNRs) into vertically-structured perovskite photoconductive photodetectors and report, as a result, perovskite-AuNR hybrid photodetectors that exhibit significant photocurrent enhancements. Ultimately it achieves a responsivity of ~320 A/W at a low driving voltage of -1 V. This is an improvement of 60% compared to the responsivity of pristine devices (~200 A/W). The high responsivity and low driving voltage place this device among the highest-performing perovskite-based thin-film photoconductive photodetectors reported. We characterized the stability and linearity of the photoresponse following repeated light/dark cycles. The hybrid device also shows a fast response (with the decay time of ~95 ns) compared to pristine devices (~230 ns). The improvements in photodetection performance are attributed to plasmon-enhanced optical absorption, as well as advances in charge extraction and transport. \u0000\u0000Metal halide perovskites have rapidly advanced thin film photovoltaic performance; ","PeriodicalId":158502,"journal":{"name":"Organic Light Emitting Materials and Devices XXII","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115090585","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Color-pure green emission is essential to realize next-generation vivid displays. Recently, solution-processed OIHPs are attracting increasing attention because of their narrow emission, and potential to be fabricated energy-efficient and low-cost in lighting and display applications. However, the perovskite light emitting diodes (LEDs) that approach Rec. 2020 standard green emission with a maximum current efficiency ≥15 cd/A have not been achieved by far. Here, we present ultrapure green LEDs based on quantum confined colloidal perovskite emitters. A spin-coated thin film of two dimensional (2D) perovskites demonstrates a high absolute photoluminescence quantum efficiency (PLQE ~ 94%). The resultant perovskite LEDs show a maximum current efficiency >20 cd/A by using a composite emission layer of colloidal 2D perovskites and poly(methyl methacrylate). As compared to Rec. 2020 standard color gamut, the green emission shows >97% color saturation in the 1931 CIE color space. We present ultra-flexible perovskite LEDs with a bending curvature radius of 2 mm by using a 50 μm thin polyimide substrate. We further demonstrate a high-efficiency large-area (30 mm2) device without compromising in the device performance. These devices show ultimate potential to realize low-cost, large-scale fabrication of the ultra-pure green LEDs for the next-generation of displays.
{"title":"High-efficiency and ultrapure-green light emitting diodes using colloidal 2D perovskites (Conference Presentation)","authors":"Sudhir Kumar, J. Jagielski, C. Shih","doi":"10.1117/12.2319160","DOIUrl":"https://doi.org/10.1117/12.2319160","url":null,"abstract":"Color-pure green emission is essential to realize next-generation vivid displays. Recently, solution-processed OIHPs are attracting increasing attention because of their narrow emission, and potential to be fabricated energy-efficient and low-cost in lighting and display applications. However, the perovskite light emitting diodes (LEDs) that approach Rec. 2020 standard green emission with a maximum current efficiency ≥15 cd/A have not been achieved by far. Here, we present ultrapure green LEDs based on quantum confined colloidal perovskite emitters. A spin-coated thin film of two dimensional (2D) perovskites demonstrates a high absolute photoluminescence quantum efficiency (PLQE ~ 94%). The resultant perovskite LEDs show a maximum current efficiency >20 cd/A by using a composite emission layer of colloidal 2D perovskites and poly(methyl methacrylate). As compared to Rec. 2020 standard color gamut, the green emission shows >97% color saturation in the 1931 CIE color space. We present ultra-flexible perovskite LEDs with a bending curvature radius of 2 mm by using a 50 μm thin polyimide substrate. We further demonstrate a high-efficiency large-area (30 mm2) device without compromising in the device performance. These devices show ultimate potential to realize low-cost, large-scale fabrication of the ultra-pure green LEDs for the next-generation of displays.","PeriodicalId":158502,"journal":{"name":"Organic Light Emitting Materials and Devices XXII","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115532505","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We will present a light emitting touch-responsive device (LETD) for instantaneous visualization of pressure mapping. The LETD integrates an organomental halide perovskite polymer composite emissive layer and a flexible silver nanowire composite transparent electrode. The composite emissive layer contains methylammonium lead bromide (MAPbBr3) nanocrystals uniformly dispersed in a polyethylene oxide matrix and emits an intense green luminescence. The polyethylene oxide matrix promotes the formation of small perovskite grains and a pinhole free composite film. The composite transparent electrode is separated from the emissive layer with a spacer. When a local pressure is applied, a Schottky contact is formed instantaneously between the metal and the emissive layer, and electroluminescence is produced at low voltages. The LETD is transparent, and can be bent when polyethylene terephthalate is used as the substrate. The device has fast response and can be pixelated to offer potentially new applications in robotics, motion detection, finger print devices, and interactive wallpapers.
{"title":"A transparent light emitting touch-responsive device (Conference Presentation)","authors":"Q. Pei","doi":"10.1117/12.2319000","DOIUrl":"https://doi.org/10.1117/12.2319000","url":null,"abstract":"We will present a light emitting touch-responsive device (LETD) for instantaneous visualization of pressure mapping. The LETD integrates an organomental halide perovskite polymer composite emissive layer and a flexible silver nanowire composite transparent electrode. The composite emissive layer contains methylammonium lead bromide (MAPbBr3) nanocrystals uniformly dispersed in a polyethylene oxide matrix and emits an intense green luminescence. The polyethylene oxide matrix promotes the formation of small perovskite grains and a pinhole free composite film. The composite transparent electrode is separated from the emissive layer with a spacer. When a local pressure is applied, a Schottky contact is formed instantaneously between the metal and the emissive layer, and electroluminescence is produced at low voltages. The LETD is transparent, and can be bent when polyethylene terephthalate is used as the substrate. The device has fast response and can be pixelated to offer potentially new applications in robotics, motion detection, finger print devices, and interactive wallpapers.","PeriodicalId":158502,"journal":{"name":"Organic Light Emitting Materials and Devices XXII","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128920685","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Organic materials that display thermally activated delayed fluorescence (TADF) are a striking class of functional materials that have witnessed a booming progress in recent years. The small ΔEST in TADF-based systems prompts highly efficient RISC from T1 to S1 states, and consequently both singlet and triplet excitons can be harvested for light emission. For the last five years, a tremendous amount of TADF molecules have been reported based on the manipulation of the intramolecular charge transfer as well as the HOMO-LUMO overlap. Beyond this strategy, there is an emerging approach that simply involves intermolecular charge transfer between physically blended electron donor and acceptor molecules for high efficiency TADF-based OLEDs (via exciplex formation). This is because the exciplex-based systems can realize relatively small ΔEST (0–0.05 eV) much more easily since the electron and hole are positioned on two different molecules, thereby giving small exchange energy. Consequently, exciplex-based OLEDs have the possibility to maximize the TADF contribution and achieve theoretical 100% internal quantum efficiency and solve the challenging issue of achieving small ΔEST in organic systems. However, research on exciplex-forming materials is still at a growing stage, and consequently, new molecules with remarkable electro and or photo-physical property are still being explored. Thus, by focusing on the development of exciplex systems, we shall have the prospective of achieving the demands for high-efficiency and high stability OLED devices. In this conference, we will report our updated results of new efficient exciplex systems, and exciplex-hosted fluorescent and phosphorescent OLEDs with high efficiency and high stability.
{"title":"High efficiency OLEDs based on exciplex (Conference Presentation)","authors":"Ken‐Tsung Wong","doi":"10.1117/12.2323782","DOIUrl":"https://doi.org/10.1117/12.2323782","url":null,"abstract":"Organic materials that display thermally activated delayed fluorescence (TADF) are a striking class of functional materials that have witnessed a booming progress in recent years. The small ΔEST in TADF-based systems prompts highly efficient RISC from T1 to S1 states, and consequently both singlet and triplet excitons can be harvested for light emission. For the last five years, a tremendous amount of TADF molecules have been reported based on the manipulation of the intramolecular charge transfer as well as the HOMO-LUMO overlap. Beyond this strategy, there is an emerging approach that simply involves intermolecular charge transfer between physically blended electron donor and acceptor molecules for high efficiency TADF-based OLEDs (via exciplex formation). This is because the exciplex-based systems can realize relatively small ΔEST (0–0.05 eV) much more easily since the electron and hole are positioned on two different molecules, thereby giving small exchange energy. Consequently, exciplex-based OLEDs have the possibility to maximize the TADF contribution and achieve theoretical 100% internal quantum efficiency and solve the challenging issue of achieving small ΔEST in organic systems. However, research on exciplex-forming materials is still at a growing stage, and consequently, new molecules with remarkable electro and or photo-physical property are still being explored. Thus, by focusing on the development of exciplex systems, we shall have the prospective of achieving the demands for high-efficiency and high stability OLED devices. In this conference, we will report our updated results of new efficient exciplex systems, and exciplex-hosted fluorescent and phosphorescent OLEDs with high efficiency and high stability.","PeriodicalId":158502,"journal":{"name":"Organic Light Emitting Materials and Devices XXII","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130092395","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Organic-inorganic halide perovskites have attracted considerable attention in the past few years because of their remarkable performance in optoelectronic devices. However, long-term stability of the materials and devices remains the biggest challenge for realistic implementation of perovskite solar cells. Although significant efforts have been carried out on the causes of degradation at the device level, yet few measurements have been made at the surface analytical level to reveal the degradation mechanisms. I’ll present our work on the effects of environmental factors, such as O2, water, and light, on the perovskite layer by monitoring the intrinsic electronic structure and compositional changes in different aging tests. This work contributes in developing better understanding of the degradation mechanisms to improve the overall stability of perovskite light emitting diodes and solar cells.
{"title":"Surface analytical investigation on stability of perovskite solar cell material (Conference Presentation)","authors":"Yongli Gao","doi":"10.1117/12.2323829","DOIUrl":"https://doi.org/10.1117/12.2323829","url":null,"abstract":"Organic-inorganic halide perovskites have attracted considerable attention in the past few years because of their remarkable performance in optoelectronic devices. However, long-term stability of the materials and devices remains the biggest challenge for realistic implementation of perovskite solar cells. Although significant efforts have been carried out on the causes of degradation at the device level, yet few measurements have been made at the surface analytical level to reveal the degradation mechanisms. I’ll present our work on the effects of environmental factors, such as O2, water, and light, on the perovskite layer by monitoring the intrinsic electronic structure and compositional changes in different aging tests. This work contributes in developing better understanding of the degradation mechanisms to improve the overall stability of perovskite light emitting diodes and solar cells.","PeriodicalId":158502,"journal":{"name":"Organic Light Emitting Materials and Devices XXII","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121785012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：