Article
Nanoscience & Nanotechnology
Ju-Hyun Yoo, Sungjin Kim, Hyeokjung Lee, Cheolmin Park, Tae-Woo Lee, Jin-Woo Park
Summary: Inorganic perovskite nanocrystals (IPNCs) have excellent optoelectronic properties, but anion migration during LED preparation and small-scale syntheses have been a problem. To address this, CsPbBr3 was synthesized in the form of nanoplatelets using only Br as the anion to eliminate anion migration and enable large-scale synthesis. The synthesis was performed at room temperature under ambient conditions. The obtained IPNPL exhibited a high photoluminescence quantum yield (PLQY) of 78% at 460 nm, and LEDs fabricated using IPNPLs showed an electroluminescence peak at 461 nm. This synthetic method has the potential to commercialize IPNCs and contribute to the next-generation display market.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Optics
Mai He, Cuihuan Ge, Kai Braun, Lanyu Huang, Xin Yang, Hepeng Zhao, Alfred J. Meixner, Xiao Wang, Anlian Pan
Summary: This study reports the fluorescence blinking phenomenon in MoS2 atomic layers in a hybrid heterostructure with quantum dots at room temperature. The single-photon nature of quantum dots in the heterostructures is demonstrated through measurement. The fluorescence blinking behavior in MoS2 is attributed to single-photon energy transfer from quantum dots to MoS2.
LASER & PHOTONICS REVIEWS
(2022)
Article
Physics, Multidisciplinary
Siyue Jin, Xingsheng Xu
Summary: In this study, single-photon and multi-photon emission from individual colloidal CdTeSe/ZnS quantum dots at room temperature were achieved. The fluorescence characteristics of these quantum dots were investigated under different excitation powers, revealing the relationship between excitation power and emission of excitons, biexcitons, and multiexcitons at a wavelength of 800 nm. The physical mechanism behind the photoluminescence of single quantum dots was analyzed.
Article
Chemistry, Multidisciplinary
Yung-Tang Chuang, Tzu-Yu Lin, Guang-Hsun Tan, Pei-En Jan, Hao-Cheng Lin, Hung-Ming Chen, Kai-Yuan Hsiao, Bo-Han Chen, Chih-Hsuan Lu, Chi-Hsuan Lee, Chun-Wei Pao, Shang-Da Yang, Ming-Yen Lu, Hao-Wu Lin
Summary: The study demonstrates the successful realization of nonblinking single photon emission in infrared-emissive halide perovskite quantum dots. These quantum dots exhibit high stability and a high single photon purity at room temperature, marking an important milestone in the field of semiconductor quantum dots.
Article
Chemistry, Physical
Nathan C. Lindquist, Ariadne Tuckmantel Bido, Alexandre G. Brolo
Summary: This paper investigates the mechanism of fluctuations in Surface Enhanced Raman Spectroscopy (SERS) signals and finds that the underlying source of these fluctuations is a complex interplay of different effects. High-speed SIF activity is present in both dry and wet nanoparticle environments, and a simple model is proposed to explain the contributions to the fluctuations.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Multidisciplinary
Lan Yu, Zhisheng Gao, He Cheng, Xin Yan, Hengyu Cao, Guangyao Guo, Huanhuan Li, Ping Li, Runfeng Chen, Ye Tao
Summary: A feasible strategy is proposed to develop colorful circularly polarized organic ultralong room temperature phosphorescence (CP-OURTP) materials from a single-component chiral molecule by introducing a chiral unit into the phosphorescence chromophore. Time-dependent colorful CP-OURTP from yellow to green is obtained by changing the intensity ratios between inherent CP-OURTP and delayed emission at different delayed times. This study provides a potential platform to prepare circularly polarized material systems showing colorful luminescent properties.
Article
Energy & Fuels
Lifei Yan, Mohammad Hossein Golestan, Wenyu Zhou, S. Majid Hassanizadeh, Carl Fredrik Berg, Amir Raoof
Summary: This article investigates the mechanism of oil phase movement during low salinity water flooding through microfluidic experiments. The study finds that different salinity contrasts result in different water fluxes and relocation of oil phases within the pore spaces. The presence of an oil-soluble surfactant enhances water flux through spontaneous emulsification. The article also proposes two scenarios to explain water transport through the oil phase.
Article
Materials Science, Multidisciplinary
Guangqiang Mei, Wei Tan, Xingxia Cui, Cong Wang, Qing Yuan, Yafei Li, Cancan Lou, Xuefeng Hou, Mengmeng Zhao, Yong Liu, Wei Ji, Xiaona Zhang, Min Feng, Limin Cao
Summary: Researchers have achieved room-temperature ferromagnetism by doping Fe into SnSe. This ferromagnetic semiconductor has a large bandgap and may be applied in next-generation information device technologies, with the advantage of scalability for industrial production.
MATERIALS TODAY PHYSICS
(2023)
Article
Nanoscience & Nanotechnology
Wenkun He, Kai-Lin Chu, Faris Abualnaja, Mervyn Jones, Zahid Durrani
Summary: Dark-field optical microscopy, combined with optical simulation based on modal diffraction theory, is used to provide non-invasive, sub-wavelength geometrical information for nanoscale etched device structures. Dark-field imaging enhances the contrast of edge diffraction, and diffraction peaks in the intensity patterns can reveal the device geometry. This approach enables non-invasive fault detection for investigating etched nanodevice morphology.
Article
Chemistry, Multidisciplinary
Maryam Bari, Hua Wu, Alexei A. Bokov, Rana Faryad Ali, Hamel N. Tailor, Byron D. Gates, Zuo-Guang Ye
Summary: This study presents a novel synthetic technique for growing single crystals of organic-inorganic halide perovskites at room temperature (or 45 degrees Celsius), achieving constant supersaturation through controlled solvent evaporation and demonstrating excellent long-term stability and high optical quality. The effects of temperature and supersaturation level on nucleation kinetics were investigated, and different growth pathways were proposed. This work provides a general strategy for designing, controlling, and optimizing the growth of high-quality halide perovskite crystals for advanced optoelectronic devices.
Article
Chemistry, Physical
Jialu Li, Dengfeng Wang, Guofeng Zhang, Changgang Yang, Wenli Guo, Xue Han, Xiuqing Bai, Ruiyun Chen, Chengbing Qin, Jianyong Hu, Liantuan Xiao, Suotang Jia
Summary: In this study, the blinking mechanism and quantum-confined Stark effect (QCSE) of single CdSe/CdS/ZnS quantum dots were investigated using single-dot PL spectroscopy. Negative surface charges were found to simultaneously suppress PL blinking and spectral diffusion, while positive surface charges changed the blinking mechanisms. Two types of QCSE were observed, and a significant QCSE-induced spectral broadening was measured.
Article
Chemistry, Multidisciplinary
Sachidananda Krishnamurthy, Ajay Singh, Zhongjian Hu, Anastasia Blake, Younghee Kim, Amita Singh, Ekaterina A. Dolgopolova, Darrick J. Williams, Andrei Piryatinski, Anton Malko, Han Htoon, Milan Sykora, Jennifer A. Hollingsworth
Summary: In this study, PbS/CdS core/shell quantum dots with single-emitter properties were successfully synthesized for room-temperature, solid-state operation in the telecom O and S bands. The research demonstrated the reasons for inhomogeneous broadening and the longer radiative decay times of core/shell structures compared to PbS cores.
Article
Multidisciplinary Sciences
Donghai Li, Chiara Trovatello, Stefano Dal Conte, Matthias Nuss, Giancarlo Soavi, Gang Wang, Andrea C. Ferrari, Giulio Cerullo, Tobias Brixner
Summary: Research on exciton-phonon coupling in single-layer transition metal dichalcogenides has shown stronger coupling compared to most other inorganic semiconductor nanostructures. Utilizing two-dimensional micro-spectroscopy, the study provides a unique tool to measure the characteristics of exciton-phonon coupling and design-relevant parameters for the development of optoelectronic devices.
NATURE COMMUNICATIONS
(2021)
Article
Materials Science, Multidisciplinary
Handong Jin, Julian A. Steele, Ruolin Cheng, Nagma Parveen, Maarten B. J. Roeffaers, Johan Hofkens, Elke Debroye
Summary: Research on organic-inorganic lead halide perovskites for use in solar cells and electro-optical devices has progressed significantly, but efficiency is still limited by deep traps in the semiconductors. Doping with chloride to passivate defects is believed to be an effective way to reduce trap densities, as evidenced by improved photoluminescence and longer lifetimes. Detailed investigation shows that chloride doping not only enhances PL intensity and lifetime, but also leads to brighter and longer ON-states in single-particle PL studies, providing additional evidence of effective trap passivation.
ADVANCED OPTICAL MATERIALS
(2021)
Article
Quantum Science & Technology
Shahram MohammadNejad, Pouya Nosratkhah, Hossein Arab
Summary: With the growth of quantum technology and its applications in non-laboratory environments, the usability of quantum systems at room temperature is becoming increasingly important. This article discusses the challenges and methods involved in creating stable and efficient single-photon emitters suitable for room temperature applications, including the history, principles, characterizing parameters, and measuring approaches related to these sources, as well as the comparison of different materials and structures.
QUANTUM INFORMATION PROCESSING
(2023)
Article
Chemistry, Physical
Samuel H. Amsterdam, Trevor LaMountain, Teodor K. Stanev, Vinod K. Sangwan, Rafael Lopez-Arteaga, Suyog Padgaonkar, Kenji Watanabe, Takashi Taniguchi, Emily A. Weiss, Tobin J. Marks, Mark C. Hersam, Nathaniel P. Stern
Summary: This study reports the morphology and temperature-dependent optical properties of pentacene films grown on hBN, showing differences in growth modality compared to SiO2 substrates, and demonstrates that using vdW materials provides a pathway for controlling optoelectronic functionality in molecular thin films.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Suyog Padgaonkar, Christopher T. Eckdahl, Jakub K. Sowa, Rafael Lopez-Arteaga, Dana E. Westmoreland, Eliot F. Woods, Shawn Irgen-Gioro, Benjamin Nagasing, Tamar Seideman, Mark C. Hersam, Julia A. Kalow, Emily A. Weiss
Summary: This paper describes reversible on-off switching of the photoluminescence intensity of CdSe quantum dots mediated by photochromic furylfulgide carboxylate molecules chemisorbed to the QDs' surfaces. The switching is enabled by different rates and yields of PL-quenching photoinduced electron transfer from the QDs to the isomers, consistent with cyclic voltammetry measurements and density functional calculations. This work demonstrates fatigue-resistant modulation of the PL of a QD-molecule complex through remote control of PET, enabling potential applications like all-optical memory, sensing, and imaging with a fast, tunable, and reversible response to light stimuli.
Article
Chemistry, Multidisciplinary
Federica Ricci, Veronica Marougail, Oleg Varnavski, Yue Wu, Suyog Padgaonkar, Shawn Irgen-Gioro, Emily A. Weiss, Theodore Goodson
Summary: This study used femtosecond time-resolved two-photon near-field scanning optical microscopy to reveal the coherence involving a single cesium lead bromide perovskite QD at room temperature. The electron coherence on a single perovskite QD was found to have a relatively long lifetime compared to other nanoparticles, possibly due to the exciton fine structure. The unique optical properties of these perovskite QDs, including bright triplet exciton states, suggest their potential for quantum computing and information processing applications.
Article
Chemistry, Physical
Suyog Padgaonkar, Paul T. Brown, Yeonjun Jeong, Charles Cherqui, Kobra N. Avanaki, Rafael Lopez-Arteaga, Shawn Irgen-Gioro, Yue Wu, Vinod K. Sangwan, George C. Schatz, Mark C. Hersam, Emily A. Weiss
Summary: This study investigates the mechanism of long-range energy transfer from quantum dots film to black phosphorus nanoflakes through an encapsulation layer. The efficient energy transfer is primarily attributed to the high areal concentration of the quantum dots film.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Chemistry, Physical
Aaron E. B. S. Stone, Shawn Irgen-Gioro, Rafael Lopez-Arteaga, Joseph T. Hupp, Emily A. Weiss
Summary: Metal-organic framework (MOF) zeolitic imidazolate framework-8 (ZIF-8) is used as a novel encapsulation material to regulate the inter-QD spacing of quantum dots (QDs), improving the photoluminescence quantum yield (PL QY) and irradiation power density of the films.
CHEMISTRY OF MATERIALS
(2022)
Article
Chemistry, Physical
Woo Je Chang, Shawn Irgen-Gioro, Suyog Padgaonkar, Rafael Lopez-Arteaga, Emily A. Weiss
Summary: This paper investigates the photosensitization mechanism of Yb3+ and Sm3+ ions in CsPbCl3 perovskite nanocrystals, revealing that the first step of photosensitization is electron transfer, followed by the formation of the emissive species Ln(3+)*. This mechanistic understanding provides a framework for selecting the right combination of host matrix and Ln(3+) species for efficient photosensitization.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Chemistry, Multidisciplinary
Samuel H. Amsterdam, Teodor K. Stanev, Luqing Wang, Qunfei Zhou, Shawn Irgen-Gioro, Suyog Padgaonkar, Akshay A. Murthy, Vinod K. Sangwan, Vinayak P. Dravid, Emily A. Weiss, Pierre Darancet, Maria K. Y. Chan, Mark C. Hersam, Nathaniel P. Stern, Tobin J. Marks
Summary: This study investigates the quenching of low-temperature defect photoluminescence in MoS2 following the deposition of metallophthalocyanines. The quenching efficiency is found to depend significantly on the identity of the phthalocyanine metal, with almost no quenching observed in the case of metal-free H2Pc.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Multidisciplinary
Jeong-Eun Park, Rafael Lopez-Arteaga, Alexander D. Sample, Charles R. Cherqui, Ioannis Spanopoulos, Jun Guan, Mercouri G. Kanatzidis, George C. Schatz, Emily A. Weiss, Teri W. Odom
Summary: This paper investigates the dynamics of hybridized states from 2D Ruddlesden-Popper perovskites coupled to plasmonic nanoparticle lattices. The coupling strength can be modulated by varying the perovskite film thickness or the superstrate refractive index. The study shows that both upper and lower polaritons have shorter lifetimes than excitons and polaritons exhibit faster excited-state dynamics when they have access to additional energy transfer channels.
Article
Chemistry, Multidisciplinary
Yishu Jiang, Rafael Lopez-Arteaga, Emily A. Weiss
Summary: This study successfully extended the scope of quantum dot photocatalyzed cycloaddition reactions to substrates without anchoring groups by introducing polyaromatic energy shuttle molecules on the quantum dot surface, achieving high yields. Compared to traditional catalyst Ir(ppy)(3), it offers the advantages of lower catalyst loading, higher stability, and reusability.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Multidisciplinary
Dana E. Westmoreland, Rafael Lopez-Arteaga, Leanna Page Kantt, Michael R. Wasielewski, Emily A. Weiss
Summary: This paper demonstrates the dynamic and reversible tuning of the optical bandgap of CdSe quantum dots through the redox states of their ligands. This has important implications for designing dynamically responsive optical sensors.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Physical
Yishu Jiang, Muwen Yang, Yue Wu, Rafael Lopez-Arteaga, Cameron R. Rogers, Emily A. Weiss
Summary: This study successfully achieved intermolecular homo- and hetero-[2 + 2] photocycloadditions of two aryl-conjugated dienes substrates using CdSe nanocrystal photocatalysts, resulting in valuable and elusive syn-trans aryl vinylcyclobutanes with high yield and selectivity.