Article
Chemistry, Multidisciplinary
Taesoo Lee, Byong Jae Kim, Hyunkoo Lee, Donghyo Hahm, Wan Ki Bae, Jaehoon Lim, Jeonghun Kwak
Summary: This study demonstrates bright and stable QLEDs on a Si substrate, achieving high brightness, efficiency, and stability through tailored interface and optimized device structure, pushing the development and application of QLEDs.
ADVANCED MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Jia-Sheng Li, Yong Tang, Zong-Tao Li, Jie-Xin Li, Xin-Rui Ding, Bin-Hai Yu, Shu-Dong Yu, Jian-Zhen Ou, Hao-Chung Kuo
Summary: The study shows that high refractive index, pore structure with comparable size, and lower QD adsorption amount contribute to enhanced QD light extraction efficiency. By optimizing packaging methods and NP mass ratio, highly efficient QD white LEDs were developed, achieving luminous efficacy comparable to phosphor-based white LEDs and paving the way for commercialization of white LEDs solely using QDs as converters in the future.
Article
Chemistry, Physical
Suhyeon Lee, Donghyo Hahm, Suk-Young Yoon, Heesun Yang, Wan Ki Bae, Jeonghun Kwak
Summary: In this study, a novel concept of QD-organic hybrid light-emitting diodes (QLEDs) is presented, which improves the performance of QLEDs and simplifies the manufacturing process, leading to higher resolution and full-color displays.
Article
Biochemistry & Molecular Biology
Ning Tu, S. W. Ricky Lee
Summary: This paper presents a large-emitting-area quantum dot light-emitting diode (QLED) fabricated using a full-solution process. The QLED exhibits a low turn-on voltage and its unique structure enables its application in inkjet printing and display applications.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Chemistry, Multidisciplinary
Guangcai Hu, Bin Xu, Aifei Wang, Yan Guo, Jiajing Wu, Faheem Muhammad, Wen Meng, Chuying Wang, Shiqi Sui, Yao Liu, Yacong Li, Ye Zhang, Yugang Zhou, Zhengtao Deng
Summary: This study successfully synthesized highly emissive organic-inorganic manganese halide perovskites using a one-pot solution-based method, demonstrating their potential application in blue light pumped white light-emitting diodes with superior white light emission quality.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Correction
Chemistry, Physical
Xiangwei Qu, Jingrui Ma, Pai Liu, Kai Wang, Xiao Wei Sun
Summary: This article points out a problem of mispresentation in the title during the publishing process and proposes a correction.
Article
Nanoscience & Nanotechnology
Mihir Manna, Sabyasachi Pramanik, Satyapriya Bhandari
Summary: We report the postsynthesis surface modification of a dual-emitting quantum dot complex (DE-QDC) nanocomposite using a blue-emitting ionic liquid (IL). The IL-modified DE-QDC exhibits tunable tricolor emission and stable white-light emission. The solid form of IL-modified DE-QDC is stable for long-term use.
ACS APPLIED NANO MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Mihir Manna, Sabyasachi Pramanik, Satyapriya Bhandari
Summary: In this study, the researchers reported a postsynthesis surface modification method for a dual emitting quantum dot complex using an ionic liquid. The modified complex showed tunable tricolor emission-based bright and stable white-light emission. The solid form of the modified complex preserved the white-light nature and structure of the quantum dots and exhibited long-term stability.
ACS APPLIED NANO MATERIALS
(2022)
Article
Chemistry, Physical
Yanping Liu, Yan Zhan, Beata Szreniawa, Katarzyna Matras-Postolek, Ping Yang
Summary: This paper demonstrates the synthesis of superior CsPbBr3 nanoplates with high stability and bright emission. The research successfully addresses the challenges of low photoluminescence efficiency and poor stability in blue-emitting perovskite nanocrystals. By adjusting the preparation conditions and promoting cation exchange reactions, the researchers were able to create dual-emissive CsPbBr3 nanoplates and fabricate a white emitting sample. This work expands the application of perovskite materials in display and lighting.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Physical
Xiangwei Qu, Jingrui Ma, Pai Liu, Kai Wang, Xiao Wei Sun
Summary: This work investigates the voltage sweep behavior of quantum dot light-emitting diodes (QLEDs). It is found that red QLEDs with ZnMgO electron transport layer (ETL) experience a drop in efficiency under consecutive voltage sweeps, while devices with ZnO ETL show an increase in efficiency. The analysis reveals that the efficiency drop in ZnMgO devices is related to hole leakage mediated by trap states on ZnMgO nanoparticles. Furthermore, the hole leakage also causes rapid lifetime degradation of ZnMgO devices.
Article
Chemistry, Multidisciplinary
Shilin Jin, He Yuan, Tao Pang, Manjia Zhang, Junyang Li, Yuanhui Zheng, Tianmin Wu, Ruidan Zhang, Zhibin Wang, Daqin Chen
Summary: This study improves the electroluminescent efficiency of lead-free double perovskites by introducing terbium doping and a guest-host strategy, achieving a significant increase in luminance and external quantum efficiency.
ADVANCED MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Hui Qi, Shujie Wang, Guangguang Huang, Yufei Tu, Chenguang Li, Xiaohong Jiang, Yan Fang, Aqiang Wang, Huaibin Shen, Zuliang Du
Summary: This research presents a unique and efficient approach for light extraction and color control of white quantum dot light-emitting diodes (W-QLEDs). The brightness of W-QLEDs is enhanced by 54.4% to an ultra-high value and the correlated color-temperature has a wider span. This approach provides a real application potential for W-QLEDs.
ADVANCED OPTICAL MATERIALS
(2022)
Article
Chemistry, Physical
Yang Li, Dejiang Zhao, Wei Huang, Zhiqiang Jiao, Lu Wang, Qingyu Huang, Peng Wang, Mengna Sun, Guangcai Yuan
Summary: An inverted red quantum dot light-emitting diode (QLED) with an organic emitting layer (EML) achieved peak current efficiency (CE) and external quantum efficiency (EQE) of 25.63 cd/A and 23.20%, respectively. The organic EML acted as an exciton harvester, capturing leaked electrons and injected holes to enhance the emission of quantum dots. Additionally, the insertion of the organic EML improved hole injection and balanced electron injection in the device, leading to a 2-fold improvement in CE and EQE compared to the control device, along with a better operational lifetime.
Article
Materials Science, Multidisciplinary
Jaber Saghaei, Manikandan Koodalingam, Paul L. Burn, Almantas Pivrikas, Paul E. Shaw
Summary: The study investigated solution-processed monochrome and white OLEDs with stable performance characteristics under different scan frequencies. By adjusting the ratio of blue, green, and red emissive materials in the light-emitting layer, white emission was achieved with optimal blend ratio providing high efficiency white OLEDs.
ORGANIC ELECTRONICS
(2022)
Article
Chemistry, Physical
Jing Chen, Qianqian Huang, Wei Lei
Summary: We report on a green, dual emissive quantum-dot light-emitting diode (QLED) using alumina-doped zinc oxide (AZO) to adjust the band offset between the cathode and QD-emitting layers, enhancing hole injection and slowing down electron injection from AZO to QD.
Article
Chemistry, Physical
Xiangwei Qu, Jingrui Ma, Pai Liu, Kai Wang, Xiao Wei Sun
Summary: This work investigates the voltage sweep behavior of quantum dot light-emitting diodes (QLEDs). It is found that red QLEDs with ZnMgO electron transport layer (ETL) experience a drop in efficiency under consecutive voltage sweeps, while devices with ZnO ETL show an increase in efficiency. The analysis reveals that the efficiency drop in ZnMgO devices is related to hole leakage mediated by trap states on ZnMgO nanoparticles. Furthermore, the hole leakage also causes rapid lifetime degradation of ZnMgO devices.
Article
Chemistry, Multidisciplinary
Hoang Long Nguyen, Thanh Nhut Do, Emek G. Durmusoglu, Merve Izmir, Ritabrata Sarkar, Sougata Pal, Oleg V. Prezhdo, Hilmi Volkan Demir, Howe-Siang Tan
Summary: In this study, the ultrafast spectral diffusion, vibronic dynamics, and energy relaxation of CdSe colloidal quantum wells (CQWs) at room temperature were measured using two-dimensional electronic spectroscopy (2DES). The energy relaxation from light-hole (LH) excitons to heavy-hole (HH) excitons was observed to occur within a time scale of approximately 210 fs. Equilibration dynamics between the spectroscopically accessible HH excitonic state and a dark state were found to take place within a time scale of approximately 160 fs. The spectral diffusion dynamics in HH excitons were analyzed using center line slope analysis, revealing a sub-200 fs decay and oscillatory features resolved at 4 and 25 meV. Quantum calculations were performed to replicate and explain the observed dynamics. The 4 meV mode was found to be in the near-critically damped regime and may mediate the transition between the bright and dark HH excitons. These findings demonstrate the capability of 2DES to comprehensively and detailedly characterize the ultrafast spectral properties in CQWs and similar nanomaterials.
Article
Optics
Huayu Wei, Qi Wei, Fan Fang, Guohong Xiang, Bingyi Tong, Chenlin Wang, Baoqing Sun, Xian Zhao, Mingjie Li, Xiao Wei Sun, Yuan Gao
Summary: This study developed environmentally friendly CQDs with high emission efficiency, achieving optical gain and lasing in the blue spectral region. The alloyed CQDs showed lower threshold and fluence, suggesting potential applications.
LASER & PHOTONICS REVIEWS
(2023)
Article
Chemistry, Physical
Qingqian Wang, Hongmei Zhu, Wei Chen, Junjie Hao, Zhaojin Wang, Jun Tang, Yingguo Yang, Xiao Wei Sun, Dan Wu, Kai Wang
Summary: This study proposes an effective strategy to achieve high CPL activity in quantum dots by introducing 2D chiral perovskite as a chiral source, providing spin polarized carriers through the CISS effect. The as-synthesized QDs/CP composites exhibit dissymmetry factors (g(lum)) up to 9.06 x 10(-3). These findings provide a useful method to achieve CPL in QDs/2D chiral perovskite heterojunctions, which could be promising in spin-optoelectronics application.
Article
Chemistry, Multidisciplinary
Hui Zhang, Xiaohu Mi, Bowen Kang, Yunkai Wu, Tingting Zhang, Pai Liu, Xiaowei Sun, Zhenglong Zhang, Ning Liu, Hongxing Xu
Summary: Colloidal nanocrystals play a significant role in optoelectronic devices and their properties can be improved through ligand modification, which can enhance charge transport and emission characteristics in LEDs.
Article
Chemistry, Physical
Farzan Shabani, Muhammad Ahmad, Satish Kumar, Savas Delikanli, Furkan Isik, Arinjoy Bhattacharya, Athos Petrou, Hilmi Volkan Demir
Summary: Two-dimensional (2D) core/shell nanoplatelets (NPLs) synthesized via the hot-injection method provide excellent thermal and chemical stability for high-temperature doping. A thermodynamic approach toward silver doping of these NPLs is proposed and demonstrated. The distribution of silver ions in the lattice of the NPLs directly affects the recombination dynamics and enables fine-tuning of the near-infrared emission.
CHEMISTRY OF MATERIALS
(2023)
Article
Chemistry, Physical
Merve Izmir, Emek G. Durmusoglu, Manoj Sharma, Farzan Shabani, Furkan Isik, Savas Delikanli, Vijay Kumar Sharma, Hilmi Volkan Demir
Summary: In this study, ytterbium (Yb) was successfully doped into cadmium selenide (CdSe) nanoplatelets (NPLs) using a modified seeded-growth method. The Yb-doped NPLs exhibited additional near-infrared (NIR) emission apart from their excitonic emission. By optimizing the dopant concentration, an impressive photoluminescence quantum yield (PL QY) of approximately 55% was achieved. Detailed elemental and optical characterizations were performed to understand the emerging photophysical properties of these Yb-doped NPLs. These lanthanide-doped CdSe NPLs emitting in the NIR range could find applications in next-generation bioimaging, night vision, and photodetection.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Optics
Yi Tian Thung, Rui Duan, Emek G. Durmusoglu, Yichen He, Lian Xiao, Calvin Xiu Xian Lee, Wen Siang Lew, Lin Zhang, Hilmi Volkan Demir, Handong Sun
Summary: Colloidal quantum wells (CQWs) are a promising gain material for optical feedback due to their unique excitonic features from 1D confinement, but current integration methods result in low laser quality. To address this, a liquid-interface kinetically driven self-assembly method is proposed to coat ultrathin CQWs onto silica microsphere cavities, achieving high-quality microlasers with a Q-factor of 13,000 at room temperature. Stable single-mode lasing output is demonstrated through evanescent field coupling in a 2D-3D microcavity configuration, highlighting the potential for future miniaturized colloidal optoelectronic and photonic applications.
LASER & PHOTONICS REVIEWS
(2023)
Article
Chemistry, Physical
Ronghuan Liu, Bihua Hu, Kai Wang, Baomin Xu, Xiao Wei Sun
Summary: Compared with polycrystalline thin films, perovskite single crystals without grain boundaries have better photovoltaic performance and stability. A green and low-cost airflow-assisted growth method has been developed for the synthesis of large quantities of high-quality and dispersed CsPbBr3 single-crystal wires under ambient conditions. This method shows great potential for optoelectronic applications and may facilitate the research of all-inorganic perovskite single crystals.
ACS APPLIED ENERGY MATERIALS
(2023)
Article
Optics
Jianxu Lan, Xiaodong Wen, Xiaowei Sun, Xixuan Liu, Yiwen Wang, Genliang Han
Summary: The study proposes a high-optomechanical-coupling-rate heterostructure with a gradient cavity, and calculates the optomechanical rates of the single mirror and hetero-optomechanical crystal nanobeam resonators. The results show that the heterostructure based on the utilization of two mirror regions achieves better confinement of the optical and mechanical modes. Additionally, it demonstrates a mechanical breathing mode at 9.75 GHz and an optical mode with a working wavelength of 1.17 μm, with an optomechanical coupling rate g(0) = 3.81 MHz between them, and an increased mechanical quality factor of 3.18 x 10(6).
Article
Physics, Applied
Guohong Xiang, Jingrui Ma, Xiangwei Qu, Kai Wang, Hoi Sing Kwok, Xiao Wei Sun
Summary: We present transparent quantum dot light-emitting diodes (QLEDs) with a current focusing structure. By depositing a SiO2 thin film to create the current focusing structure, we achieved significantly increased DC density and luminance, reaching values of over 8700 mA/cm(2) and 360,000 cd/m(2) respectively. The impact of SiO2 thickness and aperture width on emission spectra and current densities was investigated. The current focusing design demonstrates its effectiveness and potential application in other planar LED devices.
APPLIED PHYSICS LETTERS
(2023)
Review
Chemistry, Physical
Joanna Dehnel, Adi Harchol, Yahel Barak, Itay Meir, Faris Horani, Arthur Shapiro, Rotem Strassberg, Celso de Mello Donega, Hilmi Volkan Demir, Daniel R. Gamelin, Kusha Sharma, Efrat Lifshitz
Summary: Incorporating magnetic ions into semiconductor nanocrystals is a promising research field for manipulating spin-related properties. Various host materials and magnetic ions have been studied, and the impact of nanostructure engineering and ion selection in carrier-magnetic ion interactions is emphasized. The use of optically detected magnetic resonance spectroscopy provides valuable insights into the spin dynamics and physical parameters of the carrier-magnetic ion interactions.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Guanding Mei, Xiangtian Xiao, Sajjad Ahmad, Hong Lin, Yangzhi Tan, Kai Wang, Xiao Wei Sun, Wallace C. H. Choy
Summary: This study demonstrates the importance of microcavity design for improving the light extraction efficiency of Perovskite light-emitting diodes (PeLEDs). The experiment shows that a high-efficiency horizontal dipole in the microcavity is the key to improving the efficiency.
ADVANCED OPTICAL MATERIALS
(2023)
Article
Physics, Applied
Wei He, Mingyuan Huang, Xiaowei Sun
Summary: This paper presents a numerical analysis of the topological valley kink states in a two-dimensional photonic crystal, focusing on both zigzag and armchair domain walls. By manipulating the triangular holes in a honeycomb structure, inequivalent valleys were created in the momentum space. The results showed that both the zigzag and armchair interfaces can support topologically protected valley kink states, providing potential applications for valley waveguides in integrated photonics.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Optics
Phil Surman, Changxiong Zheng, Chaojian Zhang, Zhenwei Yao, Xiaochuan Yang, Wenwei Xu, Xiao Wei Sun
Summary: The availability of high-resolution display panels has made glasses-free 3D displays a viable mainstream commercial product. This paper discusses the measurement of multiview 3D displays that use a slanted lenticular screen to control light directions. Understanding the image depth of field is important, in addition to the usual parameters. The aim of the paper is to describe general theory and procedure, and not the measurement of specific displays.
