Article
Nanoscience & Nanotechnology
Sung-Joo Kwon, Soyeong Ahn, Jung-Min Heo, Dong Jin Kim, Jinwoo Park, Hae-Ryung Lee, Sungjin Kim, Huanyu Zhou, Min-Ho Park, Young-Hoon Kim, Wanhee Lee, Jeong-Yun Sun, Byung Hee Hong, Tae-Woo Lee
Summary: Graphene serves as an ionic diffusion barrier in PeLEDs to prevent the etching of ITO by acidic hole-injection layers, leading to increased photoluminescence lifetime and luminous current efficiency in optoelectronic devices.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Nanoscience & Nanotechnology
Maria Morrell, Alec Pickett, Payal Bhattacharya, Suchismita Guha, Yangchuan Xing
Summary: In this study, the optoelectronic properties of all-inorganic CsPbBr3 perovskite nanocrystals with and without RP planar faults were compared. It was found that RP-CsPbBr3 PNCs have higher exciton binding energy and longer exciton lifetimes, attributed to quantum confinement effects and spatial electron-hole separation across the RP faults. Additionally, a significant difference was observed in the up-conversion photoluminescence response of the two types of CsPbBr3 PNCs. The all-inorganic RP-CsPbBr3 PNCs were tested in light-emitting devices for the first time and showed superior performance compared to nonRP CsPbBr3 PNCs.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Multidisciplinary
Yong-Chun Ye, Yang Shen, Wei Zhou, Shi-Chi Feng, Jiang-Ying Wang, Yan-Qing Li, Jian-Xin Tang
Summary: Perovskite light-emitting diodes (PeLEDs) show promise for next-generation high-definition displays due to their excellent color purity and low power consumption. A novel strategy of interfacial molecule control is demonstrated using a bifunctional material to enhance interaction and exciton management between the perovskite and electron-transport layers. This modification layer not only passivates surface defects but also blocks interfacial exciton transfer, resulting in improved external quantum efficiencies for green, blue, and red emissions.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Ryotaro Nasu, Xun Tang, Satoru Watanabe, Chathuranganie A. M. Senevirathne, Ganbaatar Tumen-Ulzii, Toshinori Matsushima, Chihaya Adachi
Summary: Films based on 1-naphthylmethylamine (NMA) quasi-2D perovskite exhibit low lasing thresholds and small efficiency rolloff, making them promising for both optically pumped and electrically pumped lasing. The low threshold is attributed to the absence of bright exciton quenching and the shallow defect levels, which decrease nonradiative exciton recombination. The use of a circular-shaped optical resonator and small-molecule-based defect passivation further reduces the lasing threshold to one of the lowest values reported for perovskite lasers.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Jung-Yao Chen, Dong-Lin Yang, Fu-Cheng Jhuang, Yu-Han Fang, Jean-Sebastien Benas, Fang-Cheng Liang, Chi-Ching Kuo
Summary: Emulation of photonic synapses through photo-recordable devices has attracted attention for their low energy consumption and high parallelism in artificial neuromorphic networks. This study explored the impact of perovskite quantum dots on the photoresponsive characteristics of photomemory, demonstrating that quantum dots with the lowest valence band maximum and longest exciton lifetime show superior performance in terms of responsiveness and current ratios.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Nanoscience & Nanotechnology
Junlin Jia, Ruibin Wang, Haichuan Mu
Summary: CsSnBr3 photodetectors were fabricated by thermal evaporation and in situ annealing. The effects of in situ annealing on the morphology, structure, exciton dynamics, and photoresponse of the CsSnBr3 films were investigated. The annealed films showed lower exciton binding energy and trap density, as well as higher carrier mobility compared to the unannealed films. The temperature dependence of the photoresponse was attributed to the combined effect of exciton dissociation, exciton quenching through trap sites, and thermal activation of trapped carriers. In situ annealing significantly improved the photoresponse performance of the CsSnBr3 films.
Article
Nanoscience & Nanotechnology
Nagarjuna Naik Mude, Yeasin Khan, Truong Thi Thuy, Bright Walker, Jang Hyuk Kwon
Summary: This study reports the development of high-efficiency and long-lifetime inverted green cadmium-free quantum dot light-emitting diodes (QLEDs) using a stable ZnO/ZnS cascaded electron transport layer (ETL). The use of ZnO/ZnS cascaded ETL allows for reduced electron injection, improving charge balance and suppressing exciton quenching in the QD layer. The optimized devices achieved significantly improved efficiency and long lifetime compared to reference devices.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Chemistry, Physical
K. R. Pradeep, Abinaya Elumalai, Ranjani Viswanatha
Summary: This study investigates the influence of electronic structure on vibrationally assisted delayed fluorescence (VADF) in perovskite nanocrystals (NCs). By manipulating the composition and quantum confinement, it is found that the efficiency of VADF depends on the entire electronic structure. Additionally, gated photoluminescence excitation (PLE) studies demonstrate that the back-transfer of photoexcited electrons is assisted by state-specific higher excited levels that remain unchanged during size variation.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Materials Science, Multidisciplinary
Daiwen Xiao, Hei-Yui Kai, Guohua Jia, Ka-Leung Wong, Peter A. Tanner
Summary: The measurement of quantum yield (QY) is crucial for phosphors, but comparing low-temperature lifetime with room temperature lifetime may underestimate QY. Using europium ion to indicate changes in site symmetry with temperature also has limitations.
ADVANCED OPTICAL MATERIALS
(2023)
Article
Nanoscience & Nanotechnology
Haripriya Kesavan, Subhamoy Sahoo, Sanjoy Jena, Jayeeta Bhattacharyya, Debdutta Ray
Summary: The interaction of excitons in NPB with holes in pentacene was studied in a pentacene/NPB bilayer organic field-effect transistor. It was found that excitons are quenched by polarons through Forster resonance energy transfer, even if they are located on different materials. Experimental findings were supported by a steady-state three-dimensional simulation, estimating the Forster resonant energy transfer radius to be in the range of 2.3-3.0 nm at the pentacene/NPB heterojunction.
Article
Chemistry, Physical
X. R. Hou, S. D. Wang
Summary: In this study, the quasiparticle band structures and excitonic optical properties of SiC/MoSSe heterostructures were investigated using the GW + Bethe-Salpeter equation approach. The results show that all four stable structures of SiC/MoSSe heterostructures are favorable for producing high binding energy interlayer excitons. The modulation of optical dipole oscillator strength and radiative lifetimes is significant due to the different intrinsic dipole moments of MoSSe.
APPLIED SURFACE SCIENCE
(2021)
Article
Chemistry, Physical
Kyung Rock Son, Young-Hoon Kim, Dong-Hyeok Kim, Wanqi Ren, Vignesh Murugadoss, Tae Geun Kim
Summary: In this study, surface modification of ITO by electric-field-induced Ni doping treatment was demonstrated to prevent metal species diffusion and enhance the performance of PeLEDs. The PeLED fabricated using Ni-ITO as the anode showed significantly higher current efficiency and external quantum efficiency compared to the one using commercially available ITO film, providing guidelines for improving the quantum efficiencies of ITO-based devices and PeLEDs.
APPLIED SURFACE SCIENCE
(2022)
Article
Physics, Multidisciplinary
Xin Zhang, Rongtian Pang, Xinrui Hou, Shudong Wang
Summary: The stacking sequence and intrinsic dipole orientation of bilayer MoSSe can dramatically tune the electronic band structures and interlayer excitons. Interlayer excitons exhibit diverse spatial extensions, and their radiative lifetimes can be tailored within a wide range by optimizing the dipole orientation and stacking sequence.
NEW JOURNAL OF PHYSICS
(2021)
Article
Chemistry, Multidisciplinary
Yang-hao Chan, Jonah B. Haber, Mit H. Naik, Jeffrey B. Neaton, Diana Y. Qiu, Felipe H. da Jornada, Steven G. Louie
Summary: Exciton dynamics in photovoltaic and optoelectronic devices is influenced by electron-phonon and many-electron interactions, making it a challenging theoretical problem. In this study, we develop a first-principles approach and apply it to monolayer MoS2 to investigate exciton dynamics resulting from exciton-phonon coupling. We find that the selective nature of exciton-phonon coupling, determined by the internal spin structure of excitons, leads to a surprisingly long lifetime of the lowest-energy bright A exciton. Additionally, we show that optical absorption processes require a second-order perturbation theory approach, treating photon and phonon equally, which is critical for accurately describing dephasing mechanisms and obtaining exciton line widths in agreement with experiment.
Article
Chemistry, Multidisciplinary
Tariq Sheikh, Shabnum Maqbool, Parikshit Kumar Rajput, Pankaj Mandal, Angshuman Nag
Summary: The introduction of chirality in layered hybrid perovskites breaks the symmetry of their inorganic sub-lattices, resulting in intriguing optical properties. In this study, the effect of chirality on the excitonic photoluminescence of chiral (R- and S-alpha-MBA)(2)PbI4 at cryogenic temperatures was investigated. The induced chirality was found to split the excitonic emissions below 150 K. Additionally, (R- and S-alpha-MBA)(2)PbI4 exhibited wavelength-tunable second harmonic generation (SHG) that strongly depended on the polarization angle of the incident light.
CHEMICAL COMMUNICATIONS
(2022)
Article
Nanoscience & Nanotechnology
Jian-Fu Tang, Yi-Da Sie, Zong-Liang Tseng, Ja-Hon Lin, Lung-Chien Chen, Cheng-Liang Hsu
Summary: In this study, a photodetector and humidity sensor based on zinc oxide nanowires (ZnO NWs) with CsPbBr3 perovskite quantum dots (PQDs) were developed. The excellent optoelectronic properties of PQDs make them ideal for semiconductor sensors. The experimental results showed that the performance of PQD/ZnO NWs was superior to that of ZnO NWs, especially in terms of humidity response and photocurrent.
ACS APPLIED NANO MATERIALS
(2022)
Article
Crystallography
Yi-Tsung Chang, Mu-Jen Lai, Rui-Sen Liu, Shu-Chang Wang, Xiong Zhang, Lin-Jun Zhang, Yu-Hsien Lin, Shiang-Fu Huang, Lung-Chien Chen, Ray-Ming Lin
Summary: This study found that the current droop in AlGaN-based UVB light-emitting diodes is more noticeable at higher temperatures, despite both the main and parasitic peaks decreasing in intensity with increasing temperature. However, the slower temperature droop does not occur when the forward current is increased to temperatures above 298 K. After a 6000-hour aging period, the emission wavelengths do not show obvious changes, while the intensity of the parasitic peak remains nearly unchanged. Therefore, the degradation in light output power during long-term operation is not significantly correlated to the presence of the parasitic peak.
Article
Materials Science, Multidisciplinary
Ching -Ho Tien, Hui-Hsuan Tsai, Lung -Chien Chen
Summary: This study proposes a surface ligand passivation strategy to enhance the photonic characteristics and stability of CsPbBr3 perovskite nanocomposites by modifying PeQDs with didodecyl dimethyl ammonium bromide (DDAB) and gold nanoparticles (AuNPs). The incorporation of DDAB and AuNPs improved the photoluminescence intensity and external quantum efficiency of the LEDs.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2022)
Article
Engineering, Electrical & Electronic
Lung-Chien Chen, Ching-Ho Tien, Kun-Yi Lee, Zhao-Cheng Zhan
Summary: This study presents the performance of CsPbBr3 perovskite light-emitting diodes (PeLEDs) with a cesium carbonate modification layer and dual additives. The modification layer improves the crystallization of the hole transport layer and reduces resistance and impedance, enabling operation at a low level and achieving low starting voltage. The PeLEDs exhibit high luminance and external quantum efficiency at 6 V.
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2022)
Article
Chemistry, Analytical
Ching-Ho Tien, Kuan-Lin Lee, Chun-Cheng Tao, Zhan-Qi Lin, Zi-Hao Lin, Lung-Chien Chen
Summary: The study demonstrates that 2D perovskite shows higher response in vapor sensing compared to 3D perovskite, due to its large surface-to-volume ratio and reactive surface. This makes 2D perovskite more suitable for vapor sensing and trapping applications.
Editorial Material
Chemistry, Physical
Lung-Chien Chen
Article
Chemistry, Multidisciplinary
Ching-Ho Tien, Wei-Cheng Lin, Lung-Chien Chen
Summary: This study investigates the effects of different additives on the performance of perovskite solar cells. It is found that cesium can stabilize the perovskite phase, while chlorine can increase the size and crystallinity of the perovskite crystals, thereby improving the overall device performance. Additionally, modifying the interface between the hole transport layer and the perovskite layer can further enhance the photovoltaic characteristics of the perovskite solar cells.
Article
Biochemistry & Molecular Biology
Mu-Jen Lai, Yi-Tsung Chang, Shu-Chang Wang, Shiang-Fu Huang, Rui-Sen Liu, Xiong Zhang, Lung-Chien Chen, Ray-Ming Lin
Summary: This paper reports an AlGaN-based UVB-LED with peak wavelength at 293 nm that showed almost no efficiency droop in a wide temperature range. By achieving uniform distribution of injected electrons and holes within the multiple quantum wells, the J-droop phenomenon was effectively overcome.
Article
Materials Science, Multidisciplinary
Chi-Ta Li, Kuan-Lin Lee, Sea-Fue Wang, Lung-Chien Chen
Summary: This study investigates the effect of a MAPbBr3 layer in CsPbBr3 perovskite light-emitting diodes (PeLEDs). The MAPbBr3 layer, obtained from MAPbBr3 bulk crystals prepared by the inverse temperature crystallization method, serves as the evaporation source. The devices show the highest quality and performance with a 20-nm-thick MAPbBr3 layer as the nucleation and hole transport layer, leading to enhanced carrier lifetime and improved luminescence and external quantum efficiency.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Chemistry, Analytical
Lung-Chien Chen, Meng-Chi Li, Kai-Ren Chen, Yu-Jui Cheng, Xun-Ying Wu, Sih-An Chen, Meng-Jey Youh, Chien-Cheng Kuo, Yu-Xen Lin, Chih-Yen Lin, Chu-Feng Wang, Chung-Feng Huang, Shang-Yi Lin, Wen-Hung Wang, Yen-Hsu Chen, Ming-Lung Yu, Arunee Thitithanyanont, Sheng-Fan Wang, Li-Chen Su
Summary: Researchers developed a wavelength-based SPR sensor using 3D printing technology and synthesized stable NIR-emitting perovskite nanocomposites. This portable sensor can detect the coronavirus in a quick and simple manner, making it suitable for on-site detection.
ANALYTICAL CHEMISTRY
(2023)
Article
Chemistry, Analytical
Lung-Chien Chen, An-Ni Sung, Kun-Yi Lee
Summary: In this study, acetone gas sensors were fabricated using pre-annealing metal oxide zinc oxide (pa-ZnO)-doped perovskite cesium lead bromide (CsPbBr3). The optimized doping conditions were 2 mg of pa-ZnO nanopowder and pre-annealing at 300 degrees C, resulting in a sensitivity of 1726 for the ZnO-doped CsPbBr3 perovskite acetone sensor. The limit of detection for the sensor was 100 ppm, with a sensitivity of 101.
Article
Engineering, Electrical & Electronic
Meng Zhang, Zhendong Jiang, Sunbin Deng, Zhiying Chen, Xiaotong Ma, Ching-Ho Tien, Lung-Chien Chen, Man Wong, Hoi-Sing Kwok
Summary: The reliability of InSnZnO thin-film transistors (TFTs) under hot carrier (HC) stress is systematically studied in this letter. For the first time, HC degradation accompanied by recovery is observed in InSnZnO TFTs. The joint effects of acceptor-like trap state generation and electron trapping into gate insulator (GI) cause device degradation, while electron detrapping from GI and hole injection into GI contribute to device recovery. The weakening of HC effect with stress time and the vertical electric field enhancement together trigger the dominance of the recovery effect.
IEEE ELECTRON DEVICE LETTERS
(2023)
Article
Physics, Applied
Lung-Chien Chen, You-Siang Wei, Meng Zhang
Summary: We used MAPbBr(3) quantum dots and MABr salt as buffer layers to enhance the optoelectronic characteristics of CsPbBr3 perovskite light-emitting diodes (PeLEDs). The MAPbBr(3) QDs were prepared using a ligand-assisted reprecipitation method and bulk single crystals as the source material. The purified bc-MAPbBr(3) QDs and MABr salt were incorporated into the PeLED structures. The best brightness achieved was 7555 cd m(-2), and the external quantum efficiency reached 0.318%.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Lung-Chien Chen, Haixing Chang, Thangaraji Vasudevan
Summary: Scientists used guanidine hydrochloride to modify the surface of perovskite solar cells, resulting in significant improvements in their performance. The modified solar cells demonstrated increased open-circuit voltage and power conversion efficiency, indicating enhanced reliability through surface engineering.
Article
Nanoscience & Nanotechnology
Chi-Ta Li, Kuan-Lin Lee, Sea-Fue Wang, Lung-Chien Chen
Summary: This work investigates the impact of a rubidium chloride (RbCl) interlayer in CsPbBr3 perovskite light-emitting diode (LED) structures, finding that devices exhibit the best quality and performance when RbCl is used as the nucleation and carrier confinement layer.
NANOSCALE RESEARCH LETTERS
(2022)
Article
Energy & Fuels
Siddharth Sradhasagar, Omkar Subhasish Khuntia, Srikanta Biswal, Sougat Purohit, Amritendu Roy
Summary: In this study, machine learning models were developed to predict the bandgap and its character of double perovskite materials, with LGBMRegressor and XGBClassifier models identified as the best predictors. These models were further employed to predict the bandgap of novel bismuth-based transition metal oxide double perovskites, showing high accuracy, especially in the range of 1.2-1.8 eV.
Article
Energy & Fuels
Wei Shuai, Haoran Xu, Baoyang Luo, Yihui Huang, Dong Chen, Peiwang Zhu, Gang Xiao
Summary: In this study, a hybrid model based on numerical simulation and deep learning is proposed for the optimization and operation of solar receivers. By applying the model to different application scenarios and considering multiple performance objectives, small errors are achieved and optimal structure parameters and heliostat scales are identified. This approach is not only applicable to gas turbines but also heating systems.
Article
Energy & Fuels
Mubashar Ali, Zunaira Bibi, M. W. Younis, Muhammad Mubashir, Muqaddas Iqbal, Muhammad Usman Ali, Muhammad Asif Iqbal
Summary: This study investigates the structural, mechanical, and optoelectronic properties of the BaCuF3 fluoroperovskite using the first-principles modelling approach. The stability and characteristics of different cubic structures of BaCuF3 are evaluated, and the alpha-BaCuF3 and beta-BaCuF3 compounds are found to be mechanically stable with favorable optical properties for solar cells and high-frequency UV applications.
Article
Energy & Fuels
Dong Le Khac, Shahariar Chowdhury, Asmaa Soheil Najm, Montri Luengchavanon, Araa mebdir Holi, Mohammad Shah Jamal, Chin Hua Chia, Kuaanan Techato, Vidhya Selvanathan
Summary: A novel recycling system is proposed in this study to decompose and reclaim the constituent materials of organic-inorganic perovskite solar cells (PSCs). By utilizing a one-step solution process extraction approach, the chemical composition of each layer is successfully preserved, enabling their potential reuse. The proposed recycling technique helps mitigate pollution risks, minimize waste generation, and reduce recycling costs.
Article
Energy & Fuels
Peijie Lin, Feng Guo, Xiaoyang Lu, Qianying Zheng, Shuying Cheng, Yaohai Lin, Zhicong Chen, Lijun Wu, Zhuang Qian
Summary: This paper proposes an open-set fault diagnosis model for PV arrays based on 1D VoVNet-SVDD. The model accurately diagnoses various types of faults and is capable of identifying unknown fault types.
