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1.
Xiaoyu Zhang Qingsen Zeng Yuan Xiong Tianjiao Ji Chen Wang Xinyu Shen Min Lu Haoran Wang Shanpeng Wen Yu Zhang Xuyong Yang Xin Ge Wei Zhang Aleksandr P. Litvin Alexander V. Baranov Dong Yao Hao Zhang Bai Yang Andrey L. Rogach Weitao Zheng 《Advanced functional materials》2020,30(11)
Controlling the transport and minimizing charge carrier trapping at interfaces is crucial for the performance of various optoelectronic devices. Here, how electronic properties of stable, abundant, and easy‐to‐synthesized carbon dots (CDs) are controlled via the surface chemistry through a chosen ratio of their precursors citric acid and ethylenediamine are demonstrated. This allows to adjust the work function of indium tin oxide (ITO) films over the broad range of 1.57 eV, through deposition of thin CD layers. CD modifiers with abundant amine groups reduce the ITO work function from 4.64 to 3.42 eV, while those with abundant carboxyl groups increase it to 4.99 eV. Using CDs to modify interfaces between metal oxide (SnO2 and ZnO) films and active layers of solar cells and light‐emitting diodes (LEDs) allows to significantly improve their performance. Power conversion efficiency of CH3NH3PbI3 perovskite solar cells increases from 17.3% to 19.5%; the external quantum efficiency of CsPbI3 perovskite quantum dot LEDs increases from 4.8% to 10.3%; and that of CdSe/ZnS quantum dot LEDs increases from 8.1% to 21.9%. As CD films are easily fabricated in air by solution processing, the approach paves the way to a simplified manufacturing of large‐area and low‐cost optoelectronic devices. 相似文献
2.
The femtosecond-fast transport in metal–insulator–metal (MIM) tunnel diodes makes them attractive for applications such as ultra-high frequency rectenna detectors and solar cells, and mixers. These applications impose severe requirements on the diode current–voltage I(V) characteristics. For example, rectennas operating at terahertz or higher frequencies require diodes to have low resistance and adequate nonlinearity. To analyze and design MIM diodes with the desired characteristics, we developed a simulator based on the transfer-matrix method, and verified its accuracy by comparing simulated I(V) characteristics with those measured in MIM diodes that we fabricated by sputtering, and also with simulations based on the quantum transmitting boundary method. Single-insulator low-resistance diodes are not sufficiently nonlinear for efficient rectennas. Multi-insulator diodes can be engineered to provide both low resistance and substantial nonlinearity. The improved performance of multi-insulator diodes can result from either resonant tunneling or a step change in tunneling distance with voltage, either of which can be made to dominate by the appropriate choice of insulators and barrier thicknesses. The stability of the interfaces in the MIIM diodes is confirmed through a thermodynamic analysis. 相似文献
3.
Sung‐Bum Bae Sung‐Bok Kim Dong‐Churl Kim Eun Soo Nam Sung‐Mook Lim Jeong‐Hwan Son Yi‐Sang Jo 《ETRI Journal》2013,35(4):566-570
In this paper, we demonstrate the capabilities of 380‐nm ultraviolet (UV) light‐emitting diodes (LEDs) using metal organic chemical vapor deposition. The epi‐structure of these LEDs consists of InGaN/AlGaN multiple quantum wells on a patterned sapphire substrate, and the devices are fabricated using a conventional LED process. The LEDs are packaged with a type of surface mount device with Al‐metal. A UV LED can emit light at 383.3 nm, and its maximum output power is 118.4 mW at 350 mA. 相似文献
4.
Sanjun Yang Kailang Liu Wei Han Liang Li Fakun Wang Xing Zhou Huiqiao Li Tianyou Zhai 《Advanced functional materials》2020,30(7)
P‐n junctions based on two dimensional (2D) van der Waals (vdW) heterostructure are one of the most promising alternatives in next‐generation electronics and optoelectronics. By choosing different 2D transition metal dichalcogenides (TMDCs), the p‐n junctions have tailored energy band alignments and exhibit superior performance as photodetectors. The p‐n diodes working at reverse bias commonly have high detectivity due to suppressed dark current but suffer from low responsivity resulting from small quantum efficiency. Greater build‐in electric field in the depletion layer can improve the quantum efficiency by reducing recombination of charge carriers. Herein, Cu9S5, a novel p‐type semiconductor with direct bandgap and high optical absorption coefficient, is synthesized by salt‐assisted chemical vapor deposition (CVD) method. The high density of holes in Cu9S5 endows the constructed p‐n junction, Cu9S5/MoS2, with strong build‐in electric field according to Anderson heterojunction model. Consequently, the Cu9S5/MoS2 p‐n heterojunction has low dark current at reverse bias and high photoresponse under illumination due to the efficient charge separation. The Cu9S5/MoS2 photodetector exhibits good photodetectivity of 1.6 × 1012 Jones and photoresponsivity of 76 A W?1 under illumination. This study demonstrates Cu9S5 as a promising p‐type semiconductor for high‐performance p‐n heterojunction diodes. 相似文献
5.
Hadhi Wijaya Daryl Darwan Xiaofei Zhao Evon Woan Yuann Ong Kang Rui Garrick Lim Tian Wang Li Jun Lim Khoong Hong Khoo Zhi‐Kuang Tan 《Advanced functional materials》2020,30(4)
Near‐infrared (NIR) lighting plays an increasingly important role in new facial recognition technologies and eye‐tracking devices, where covert and nonvisible illumination is needed. In particular, mobile or wearable gadgets that employ these technologies require electronic lighting components with ultrathin and flexible form factors that are currently unfulfilled by conventional GaAs‐based diodes. Colloidal quantum dots (QDs) and emerging perovskite light‐emitting diodes (LEDs) may fill this gap, but generally employ restricted heavy metals such as cadmium or lead. Here, a new NIR‐emitting diode based on heavy‐metal‐free In(Zn)As–In(Zn)P–GaP–ZnS quantum dots is reported. The quantum dots are prepared with a giant shell structure, enabled by a continuous injection synthesis approach, and display intense photoluminescence at 850 nm with a high quantum efficiency of 75%. A postsynthetic ligand exchange to a shorter‐chain 1‐mercapto‐6‐hexanol (MCH) affords the QDs with processability in polar solvents as well as an enhanced charge‐transport performance in electronic devices. Using solution‐processing methods, an ITO/ZnO/PEIE/QD/Poly‐TPD/MoO3/Al electroluminescent device is fabricated and a high external quantum efficiency of 4.6% and a maximum radiance of 8.2 W sr?1 m?2 are achieved. This represents a significant leap in performance for NIR devices employing a colloidal III–V semiconductor QD system, and may find significant applications in emerging consumer electronic products. 相似文献
6.
Large‐Area Bilayer ReS2 Film/Multilayer ReS2 Flakes Synthesized by Chemical Vapor Deposition for High Performance Photodetectors
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Muhammad Hafeez Lin Gan Huiqiao Li Ying Ma Tianyou Zhai 《Advanced functional materials》2016,26(25):4551-4560
Rhenium disulfide (ReS2) is attracting more and more attention for its thickness‐depended direct band gap. As a new appearing 2D transition metal dichalcogenide, the studies on synthesis method via chemical vapor deposition (CVD) is still rare. Here a systematically study on the CVD growth of continuous bilayer ReS2 film and single crystalline hexagonal ReS2 flake, as well as their corresponding optoelectronic properties is reported. Moreover, the growth mechanism has been proposed, accompanied with simulation study. High‐performance photodetector based on ReS2 flake shows a high responsivity of 604 A·W?1, high external quantum efficiency of 1.50 × 105 %, and fast response time of 2 ms. ReS2 film‐based photodetector exhibits weaker performance than the flake one; however, it still demonstrates a much faster response time (≈103 ms) than other reported CVD‐grown ReS2‐based photodetector (≈104–105 ms). Such good properties of ReS2 render it a promising future in 2D optoelectronics. 相似文献
7.
Jiadong Zhou Bijun Tang Junhao Lin Danhui Lv Jia Shi Linfeng Sun Qingsheng Zeng Lin Niu Fucai Liu Xiaowei Wang Xinfeng Liu Kazu Suenaga Chuanhong Jin Zheng Liu 《Advanced functional materials》2018,28(31)
In recent years, heterostructures formed in transition metal dichalcogenides (TMDs) have attracted significant attention due to their unique physical properties beyond the individual components. Atomically thin TMD heterostructures, such as MoS2‐WS2, MoS2‐MoSe2, MoS2‐WSe2, and WSe2‐WS2, are synthesized so far via chemical vapor deposition (CVD) method. Engineering the morphology of domains including size and shape, however, still remains challenging. Here, a one‐step CVD strategy on the morphology engineering of MoS2 and WS2 domains within the monolayer MoS2‐WS2 lateral heterostructures through controlling the weight ratio of precursors, MoO3 and WO3, as well as tuning the reaction temperature is reported. Not only can the size ratio in terms of area between WS2 and MoS2 domains be easily controlled from less than 1 to more than 20, but also the overall heterostructure size can be tuned from several to hundreds of micrometers. Intriguingly, the quantum well structure, a WS2 stripe embedded in the MoS2 matrix, is also observed in the as‐synthesized heterostructures, offering opportunities to study quantum confinement effects and quantum well applications. This approach paves the way for the large‐scale fabrication of MoS2‐WS2 lateral heterostructures with controllable domain morphology, and shall be readily extended to morphology engineering of other TMD heterostructures. 相似文献
8.
Seong Keun Kim Sang Woon Lee Jeong Hwan Han Bora Lee Seungwu Han Cheol Seong Hwang 《Advanced functional materials》2010,20(18):2989-3003
The recent progress in the metal‐insulator‐metal (MIM) capacitor technology is reviewed in terms of the materials and processes mostly for dynamic random access memory (DRAM) applications. As TiN/ZrO2‐Al2O3‐ZrO2/TiN (ZAZ) type DRAM capacitors approach their technical limits, there has been renewed interest in the perovskite SrTiO3, which has a dielectric constant of >100, even at a thickness ~10 nm. However, there are many technical challenges to overcome before this type of MIM capacitor can be used in mass‐production compatible processes despite the large advancements in atomic layer deposition (ALD) technology over the past decade. In the mean time, rutile structure TiO2 and Al‐doped TiO2 films might find space to fill the gap between ZAZ and SrTiO3 MIM capacitors due to their exceptionally high dielectric constant among binary oxides. Achieving a uniform and dense rutile structure is the key technology for the TiO2‐based dielectrics, which depends on having a dense, uniform and smooth RuO2 layer as bottom electrode. Although the Ru (and RuO2) layers grown by ALD using metal‐organic precursors are promising, recent technological breakthroughs using the RuO4 precursor made a thin, uniform, and denser Ru and RuO2 layer on a TiN electrode. A minimum equivalent oxide thickness as small as 0.45 nm with a low enough leakage current was confirmed, even in laboratory scale experiments. The bulk dielectric constant of ALD SrTiO3 films, grown at 370 °C, was ~150 even with thicknesses ≤15 nm. The recent development of novel group II precursors made it possible to increase the growth rate largely while leaving the electrical properties of the ALD SrTiO3 film intact. This is an important advancement toward the commercial applications of these MIM capacitors to DRAM as well as to other fields, where an extremely high capacitor density and three‐dimensional structures are necessary. 相似文献
9.
Joy Cho Matin Amani Der‐Hsien Lien Hyungjin Kim Matthew Yeh Vivian Wang Chaoliang Tan Ali Javey 《Advanced functional materials》2020,30(6)
Monolayer 2D transition metal dichalcogenides (TMDCs) have shown great promise for optoelectronic applications due to their direct bandgaps and unique physical properties. In particular, they can possess photoluminescence quantum yields (PL QY) approaching unity at the ultimate thickness limit, making their application in light‐emitting devices highly promising. Here, large‐area WS2 grown via chemical vapor deposition is synthesized and characterized for visible (red) light‐emitting devices. Detail optical characterization of the synthesized films is performed, which show peak PL QY as high as 12%. Electrically pumped emission from the synthetic WS2 is achieved utilizing a transient‐mode electroluminescence device structure, which consists of a single metal–semiconductor contact and alternating gate fields to achieve bipolar emission. Utilizing this aforementioned structure, a centimeter‐scale ( ≈ 0.5 cm2) visible (640 nm) display is demonstrated, fabricated using TMDCs to showcase the potential of this material system for display applications. 相似文献
10.
Henry Medina Yung‐Chang Lin Chuanhong Jin Chun‐Chieh Lu Chao‐Hui Yeh Kun‐Ping Huang Kazu Suenaga John Robertson Po‐Wen Chiu 《Advanced functional materials》2012,22(10):2123-2128
Conventional methods to prepare large‐area graphene for transparent conducting electrodes involve the wet etching of the metal catalyst and the transfer of the graphene film, which can degrade the film through the creation of wrinkles, cracks, or tears. The resulting films may also be obscured by residual metal impurities and polymer contaminants. Here, it is shown that direct growth of large‐area flat nanographene films on silica can be achieved at low temperature (400 °C) by chemical vapor deposition without the use of metal catalysts. Raman spectroscopy and TEM confirm the formation of a hexagonal atomic network of sp2‐bonded carbon with a domain size of about 3–5 nm. Further spectroscopic analysis reveals the formation of SiC between the nanographene and SiO2, indicating that SiC acts as a catalyst. The optical transmittance of the graphene films is comparable with transferred CVD graphene grown on Cu foils. Despite the fact that the electrical conductivity is an order of magnitude lower than CVD graphene grown on metals, the sheet resistance remains 1–2 orders of magnitude better than well‐reduced graphene oxides. 相似文献
11.
12.
CdS Nanoribbon‐Based Resistive Switches with Ultrawidely Tunable Power by Surface Charge Transfer Doping
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Zhibin Shao Jiansheng Jie Tianhao Jiang Xiaofeng Wu Ke Li Feifei Xia Xiujuan Zhang Xiaohong Zhang 《Advanced functional materials》2018,28(16)
Traditional metal–insulator–metal (MIM)‐based resistive switches (RS) possess a high operating current, which can be read directly without an amplifier yet will inevitably produce large power consumption. Rational control of the energy consumption of RS devices is surely desirable to achieve the energy‐efficient purpose in a variety of practical applications. Here a surface charge transfer doping (SCTD) strategy is reported to manipulate the operating current as well as power consumption of the RS devices by using doped CdS nanoribbon (NR) as a rheostat. By controlling the concentration of surface dopant of MoO3, the conductivity of doped CdS NR can be tuned in a wide range of nine orders of magnitude, showing the transition from insulator to semiconductor and to conductor. On the basis of CdS NRs with controllable conductivity, the as‐fabricated RS devices exhibit an ultrawidely tunable‐power consumption from 1 nW, the lowest value reported so far, to 0.1 mW, which is close to the typical values of MIM‐based RS devices. In view of the high controllability of the SCTD method, this work opens up unique opportunities for future energy‐efficient, performance‐tunable, and multifunctional RS devices based on semiconductor nanostructures. 相似文献
13.
Tian‐Chi Chen Meng‐Qiang Zhao Qiang Zhang Gui‐Li Tian Jia‐Qi Huang Fei Wei 《Advanced functional materials》2013,23(40):5066-5073
The high‐end applications of single‐walled carbon nanotubes (SWCNTs) are hindered by the existence of large amount of impurities, especially the graphene layers encapsulating metal nanoparticles (metal@C NPs). The role of working metal catalysts during chemical vapor deposition (CVD) growth and post purifications by oxidation are not yet fully understood. Herein, the in situ monitoring the role of working metal catalyst NPs for ultrahigh purity SWCNTs by CVD growth and CO2 purifications is carried out in an online thermogravimetric reactor attached with a mass spectrometer. The growth of SWCNTs almost stops after the initial 2 min, then, the mass increase of the samples mainly originates from the metal@CNP formation. Therefore, high‐purity SWCNTs (98.5 wt%) with few metal@CNPs can be available by 2 min CVD growth. Furthermore, CO2 oxidation of the SWCNTs is also investigated in a thermogravimetric reactor. The oxidation of graphene layers surrounding the metal NPs and the SWCNTs occurs during distinct temperature ranges, which is further demonstrated by the significant differences among their oxidation activation energies. Ultrahigh purity of SWNCT with a carbon content of 99.5 wt% can be available by a CO2‐assited purification method. The in situ study of the CVD growth and CO2 oxidation of SWCNTs provides the real time information on the working catalyst during reaction and the reactivity information of metal@CNPs and SWCNTs under an oxidizing atmosphere. The success for the preparation of high‐purity SWCNT lies in the efficient growth of SWCNTs with a low amount of nanocarbon impurities and partial oxidation of metal@CNPs by catalytic CO2 oxidation with proper operation parameters. 相似文献
14.
Solution‐Processable Hosts Constructed by Carbazole/PO Substituted Tetraphenylsilanes for Efficient Blue Electrophosphorescent Devices
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He Liu Qing Bai Liang Yao Dehua Hu Xiangyang Tang Fangzhong Shen Huanhuan Zhang Yu Gao Ping Lu Bing Yang Yuguang Ma 《Advanced functional materials》2014,24(37):5881-5888
Two new solution‐processable wide bandgap materials, bis(4‐((4‐(9‐H‐carbazol‐9‐yl)phenyl)diphenylsilyl)phenyl)(phenyl)phosphine oxide (CS2PO) and bis(4‐((4‐(9‐H‐(3,9′‐bicarbazol)‐9‐yl)phenyl)diphenylsilyl)phenyl)(phenyl)phosphine oxide (DCS2PO), have been developed for blue phosphorescent light‐emitting diodes by coupling an electron‐donating carbazole moiety and an electron‐accepting PO unit together via double‐silicon bridges. Both of them have been characterized as having high glass transition temperatures of 159–199 °C, good solubility in common organic solvent (20 mg mL?1), wide optical gap (3.37–3.55 eV) and high triplet energy levels (2.97–3.04 eV). As compared with their corresponding single‐silicon bridged compounds, this design strategy of extending molecular structure endows CS2PO and DCS2PO with higher thermal stability, better solution processability and more stable film morphology without lowering their triplet energies. As a result, DCS2PO/FIrpic doped blue phosphorescent device fabricated by spin‐coating method shows the best electroluminescent performance with a maximum current efficiency of 26.5 cd A?1, a maximum power efficiency of 8.66 lm W?1, and a maximum external quantum efficiency of 13.6%, which is one of the highest efficiencies among small molecular devices with the same deposition process and device configuration. 相似文献
15.
Hee‐Bok Kang Suk‐Kyoung Hong Yong‐Wook Song Man Young Sung Bokgil Choi Jinyong Chung Jong‐Wook Lee 《ETRI Journal》2008,30(6):826-832
The metal‐ferroelectric‐metal (MFM) capacitor in the ferroelectric random access memory (FeRAM) embedded RFID chip is used in both the memory cell region and the peripheral analog and digital circuit area for capacitance parameter control. The capacitance value of the MFM capacitor is about 30 times larger than that of conventional capacitors, such as the poly‐insulator‐poly (PIP) capacitor and the metal‐insulator‐metal (MIM) capacitor. An MFM capacitor directly stacked over the analog and memory circuit region can share the layout area with the circuit region; thus, the chip size can be reduced by about 60%. The energy transformation efficiency using the MFM scheme is higher than that of the PIP scheme in RFID chips. The radio frequency operational signal properties using circuits with MFM capacitors are almost the same as or better than with PIP, MIM, and MOS capacitors. For the default value specification requirement, the default set cell is designed with an additional dummy cell. 相似文献
16.
In Situ Construction of 3D Interconnected FeS@Fe3C@Graphitic Carbon Networks for High‐Performance Sodium‐Ion Batteries
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Qinghong Wang Wenchao Zhang Can Guo Yajie Liu Chao Wang Zaiping Guo 《Advanced functional materials》2017,27(41)
Iron sulfides have been attracting great attention as anode materials for high‐performance rechargeable sodium‐ion batteries due to their high theoretical capacity and low cost. In practice, however, they deliver unsatisfactory performance because of their intrinsically low conductivity and volume expansion during charge–discharge processes. Here, a facile in situ synthesis of a 3D interconnected FeS@Fe3C@graphitic carbon (FeS@Fe3C@GC) composite via chemical vapor deposition (CVD) followed by a sulfuration strategy is developed. The construction of the double‐layered Fe3C/GC shell and the integral 3D GC network benefits from the catalytic effect of iron (or iron oxides) during the CVD process. The unique nanostructure offers fast electron/Na ion transport pathways and exhibits outstanding structural stability, ensuring fast kinetics and long cycle life of the FeS@Fe3C@GC electrodes for sodium storage. A similar process can be applied for the fabrication of various metal oxide/carbon and metal sulfide/carbon electrode materials for high‐performance lithium/sodium‐ion batteries. 相似文献
17.
Chang‐Woo Kwon Ji‐Won Son Jong‐Ho Lee Hyun‐Mi Kim Hae‐Weon Lee Ki‐Bum Kim 《Advanced functional materials》2011,21(6):1154-1159
Micro‐solid oxide fuel cells (μ‐SOFCs) are fabricated on nanoporous anodic aluminum oxide (AAO) templates with a cell structure composed of a 600‐nm‐thick AAO free‐standing membrane embedded on a Si substrate, sputter‐deposited Pt electrodes (cathode and anode) and an yttria‐stabilized zirconia (YSZ) electrolyte deposited by pulsed laser deposition (PLD). Initially, the open circuit voltages (OCVs) of the AAO‐supported μ‐SOFCs are in the range of 0.05 V to 0.78 V, which is much lower than the ideal value, depending on the average pore size of the AAO template and the thickness of the YSZ electrolyte. Transmission electron microscopy (TEM) analysis reveals the formation of pinholes in the electrolyte layer that originate from the porous nature of the underlying AAO membrane. In order to clog these pinholes, a 20‐nm thick Al2O3 layer is deposited by atomic layer deposition (ALD) on top of the 300‐nm thick YSZ layer and another 600‐nm thick YSZ layer is deposited after removing the top intermittent Al2O3 layer. Fuel cell devices fabricated in this way manifest OCVs of 1.02 V, and a maximum power density of 350 mW cm?2 at 500 °C. 相似文献
18.
Metal‐Insulator Transition in ALD VO2 Ultrathin Films and Nanoparticles: Morphological Control
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Antony P. Peter Koen Martens Geert Rampelberg Michael Toeller James M. Ablett Johan Meersschaut Daniel Cuypers Alexis Franquet Christophe Detavernier Jean‐Pascal Rueff Marc Schaekers Sven Van Elshocht Malgorzata Jurczak Christoph Adelmann Iuliana P. Radu 《Advanced functional materials》2015,25(5):679-686
Nanoscale morphology of vanadium dioxide (VO2) films can be controlled to realize smooth ultrathin (<10 nm) crystalline films or nanoparticles with atomic layer deposition, opening doors to practical VO2 metal‐insulator transition (MIT) nanoelectronics. The precursor combination, the valence of V, and the density for as‐deposited VO2 films, as well as the postdeposition crystallization annealing conditions determine whether a continuous thin film or nanoparticle morphology is obtained. It is demonstrated that the films and particles possess both a structural and an electronic transition. The resistivity of ultrathin films changes by more than two orders of magnitude across the MIT, demonstrating their high quality. 相似文献
19.
“Regioselective Deposition” Method to Pattern Silver Electrodes Facilely and Efficiently with High Resolution: Towards All‐Solution‐Processed,High‐Performance,Bottom‐Contacted,Flexible, Polymer‐Based Electronics
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Deyang Ji Lang Jiang Yunlong Guo Huanli Dong Jianpu Wang Huajie Chen Qing Meng Xiaolong Fu Guofeng Tian Dezhen Wu Gui Yu Yunqi Liu Wenping Hu 《Advanced functional materials》2014,24(24):3783-3789
“Regioselectivity deposition” method is developed to pattern silver electrodes facilely and efficiently by solution‐process with high resolution (down to 2 μm) on different substrates in A4 paper size. With the help of this method, large‐area, flexible, high‐performance polymer field‐effect transistors based on the silver electrodes and polyimide insulator are fabricated with bottom‐contact configuration by all‐solution processes. The polymer devices exhibit high performance with average field‐effect mobility over 1.0 cm2 V?1 s?1 (the highest mobility up to 1.5 cm2 V?1 s?1) and excellent environmental stability and flexibility, indicating the cost effectiveness of this method for practical applications in organic electronics. 相似文献
20.
High‐performance, blue, phosphorescent organic light‐emitting diodes (PhOLEDs) are achieved by orthogonal solution‐processing of small‐molecule electron‐transport material doped with an alkali metal salt, including cesium carbonate (Cs2CO3) or lithium carbonate (Li2CO3). Blue PhOLEDs with solution‐processed 4,7‐diphenyl‐1,10‐phenanthroline (BPhen) electron‐transport layer (ETL) doped with Cs2CO3 show a luminous efficiency (LE) of 35.1 cd A?1 with an external quantum efficiency (EQE) of 17.9%, which are two‐fold higher efficiency than a BPhen ETL without a dopant. These solution‐processed blue PhOLEDs are much superior compared to devices with vacuum‐deposited BPhen ETL/alkali metal salt cathode interfacial layer. Blue PhOLEDs with solution‐processed 1,3,5‐tris(m‐pyrid‐3‐yl‐phenyl)benzene (TmPyPB) ETL doped with Cs2CO3 have a luminous efficiency of 37.7 cd A?1 with an EQE of 19.0%, which is the best performance observed to date in all‐solution‐processed blue PhOLEDs. The results show that a small‐molecule ETL doped with alkali metal salt can be realized by solution‐processing to enhance overall device performance. The solution‐processed metal salt‐doped ETLs exhibit a unique rough surface morphology that facilitates enhanced charge‐injection and transport in the devices. These results demonstrate that orthogonal solution‐processing of metal salt‐doped electron‐transport materials is a promising strategy for applications in various solution‐processed multilayered organic electronic devices. 相似文献