Article
Materials Science, Multidisciplinary
Ananthakumar Soosaimanickam, Hamid Pashaei Adl, Vladimir Chirvony, Pedro J. Rodriguez-Canto, Juan P. Martinez-Pastor, Rafael Abargues
Summary: Colloidal cesium lead bromide perovskite nanocrystals are densely packed into thin films using the doctor blade method, and their optical properties are significantly improved through ligand exchange with sodium and potassium nitrate. Passivation of ligand-induced surface defects by sodium and potassium cations and nitrate leads to enhanced photoluminescence and carrier lifetime properties. Alkali metal nitrate salts treated films exhibit higher photoluminescence intensity and longer carrier lifetime compared to the pristine capped films, indicating their potential for achieving defect-free inorganic perovskite nanocrystal films.
Article
Chemistry, Multidisciplinary
Rakesh Kumar Behera, Koushik Jagadish, Sanjib Shyamal, Narayan Pradhan
Summary: Designing heterostructures of soft ionic nanocrystals with metallic or covalent nanostructures presents challenges. This study reports the formation of epitaxial heterostructures of orthorhombic CsPbBr3 and cubic Pt. The key parameters for obtaining such nanocrystal heterostructures are the appropriate facets of perovskite nanocrystals and high-temperature reaction.
Article
Chemistry, Physical
Maryam Bari, Alexei A. Bokov, Gary W. Leach, Zuo-Guang Ye
Summary: This study explores the importance of temperature-dependent spontaneous strain in halide perovskites. By investigating the optical properties, X-ray diffraction, and dielectric properties of CsPbBr3 single crystals, it is found that this material undergoes two phase transitions and exhibits ferroelastic behavior under external electric field or stress. Furthermore, it is discovered that anomalies in certain properties previously attributed to additional phase transitions are actually artifacts caused by changes in the ferroelastic domain structure and internal strain.
CHEMISTRY OF MATERIALS
(2023)
Article
Energy & Fuels
Yudong Zhang, Wenchao Zhang, Ying Ye, Kai Li, Xiao Gong, Chao Liu
Summary: CsPbX3 perovskite nanocrystals have potential application in LSCs, but their instability in ambient environment limits practical use. This study demonstrates high optical efficiency LSCs by embedding CsPbBr3 nanocrystals in glass sheets, which also provide protection for the nanocrystals.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2022)
Article
Chemistry, Physical
Saptarshi Mandal, Swarnali Ghosh, Soumen Mukherjee, Debjit Roy, Chayan K. De, Kingshuk Mukhuti, Prasun K. Mandal
Summary: The study demonstrates that CsPbBr3 perovskite nanocrystals exhibit high optical robustness and the ability to depict ensemble optical behavior, which are crucial for their prospective applications.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Engineering, Environmental
Xiaobing Tang, Nadeesha Lakmali Kothalawala, Yulin Zhang, Dali Qian, Doo Young Kim, Fuqian Yang
Summary: This study demonstrates the successful production of microsized CsPbBr3 crystals and CsPbBr3 nanocrystals using deionized water as the precursor solvent, showing their potential applications in flexible LCD backlights. The nanocrystals exhibit high PL quantum yields and improved stability, providing a promising avenue for environmentally-friendly and bending-endurable backlight films in flexible display applications.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Nanoscience & Nanotechnology
Radha Rathod, Ranjan Das, Manash R. Das, Pralay K. Santra
Summary: Lead halide perovskite nanocrystals (LHP NCs) have promising optoelectronic properties but poor ambient stability. Plasma treatment is an effective method to enhance stability without compromising charge transport. However, longer duration of plasma treatment can decrease photoluminescence and make the NCs hydrophilic. This study investigates the chemistry behind stability enhancement during plasma treatment and its impact on photoluminescence intensity.
ACS APPLIED NANO MATERIALS
(2022)
Article
Chemistry, Physical
Sungyeon Heo, Kwangdong Roh, Fengyu Zhang, Steven E. Tignor, Andrew B. Bocarsly, Antoine Kahn, Barry P. Rand
Summary: Electrochemical n-doping of halide perovskites is challenging due to limited electrochemical stability. In this study, we report the successful electrochemical n-doping of CsPbBr3 nanocrystal films within stable potential windows. The nanocrystal films show enhanced n-doping properties compared to bulk films, and the n-doped films exhibit Fermi level shifts and increased conductivity and photoluminescence intensity.
ACS ENERGY LETTERS
(2022)
Article
Chemistry, Multidisciplinary
Hengwei Qiu, Fu Li, Shan He, Ran Shi, Yaoyao Han, Hannikezi Abudukeremu, Lin Zhang, Yan Zhang, Song Wang, Wangyu Liu, Chao Ma, Honghua Fang, Run Long, Kaifeng Wu, Hao Zhang, Jinghong Li
Summary: This study reports the synthesis of uniform, epitaxially grown CsPbBr3/CdS Janus nanocrystal heterostructures with ultrafast charge separation across the electronically coupled interface. Each Janus nanocrystal contains a CdS domain that grows exclusively on a single {220} facet of CsPbBr3 nanocrystals. The promoted charge separation and extraction in epitaxial Janus nanocrystals leads to photoconductors with drastically improved responsivity and detectivity, which is promising for ultrasensitive photodetection.
Article
Chemistry, Physical
Ekashmi Rathore, Kaushik Kundu, Krishnendu Maji, Anustoop Das, Kanishka Biswas
Summary: This study demonstrates the integration of CsPbBr3 nanocrystals and Bi2O2Se ultrathin nanosheets to explore their optical properties in nano-heterostructures. The formation of heterostructures was confirmed, and the bonding interactions were studied. Photoluminescence quenching was observed in the mixed-dimensional CsPbBr3@Bi2O2Se heterostructure, with charge transfer characteristics examined using time-resolved PL at different temperatures.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Chemistry, Physical
Jonathan De Roo
Summary: This article provides a perspective from a nanochemist on the field of colloidal nanocrystals, with a specific focus on nanocrystal synthesis. It discusses the chemistry involved with precursors, ligands, and solvents, as well as different crystallization mechanisms. The article also addresses the need for standard reporting practices in the field and encourages researchers to consider chemical equations and reaction by-products.
CHEMISTRY OF MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Cedric R. Mayer, Hugo Levy-Falk, Maxime Remond, Gaelle Trippe-Allard, Frederic Fossard, Maxime Vallet, Marc Lepeltier, Nicolas Guiblin, Jean-Sebastien Lauret, Damien Garrot, Emmanuelle Deleporte
Summary: A new synthetic method for preparing highly calibrated CsPbBr3 nanocrystal perovskites is described, which is analyzed using high-resolution scanning transmission electron microscopy. This soft chemistry-based method enables large-scale production of nanocrystals. The monodisperse nanocrystals can be used for the deposition of homogeneous films, providing new opportunities for the next generation of optoelectronic devices.
CHEMICAL COMMUNICATIONS
(2022)
Article
Engineering, Electrical & Electronic
Yue Han, Rong Wen, Ting Ji, Wenyan Wang, Linlin Shi, Yuying Hao, Guohui Li, Yanxia Cui
Summary: In this study, high-performance metal-semiconductor-metal photodetectors (PDs) based on all-inorganic CsPbBr3 perovskite nanocrystals (NCs) were demonstrated using a low-cost titanium nitride (TiN) electrode. The PD with TiN electrode showed a dark current as low as that with Au electrode, while the PD with Ag electrode was hundreds of times inferior. Moreover, the TiN electrode PD exhibited better stability compared to the device with Ag electrode. This work contributes to the development of low-cost, high-performance PDs based on solution-processed semiconductors.
IEEE SENSORS JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Souvik Banerjee, Suman Bera, Narayan Pradhan
Summary: This study investigates the surface reconstruction of preformed CsPbBr3 nanocrystals using selected ligands. The results show that the flat edges and planar facets of the orthorhombic nanocrystals can be transformed into wavy structures by adding oleylammmonium bromide. This surface reconstruction is also observed in multisegmented platelets and large-sized platelets.
Article
Chemistry, Physical
Jieting Ban, Ying Yu, Peng Yue, Lanqi Lian, Cheng Xu, Lei Guo, Shao-Ding Liu
Summary: This study experimentally demonstrates that the two-photon luminescence of individual CsPbBr3 nanocrystal superlattices is enhanced by about 16 times compared to randomly oriented nanocrystal films. The nanocrystal superlattices possess a 4-fold symmetry similar to single-crystal film structures. They exhibit broad nonlinear absorption responses, leading to wide-range interband photoluminescence below the bandgap. Moreover, the two-photon absorption coefficient can reach 0.644 cm/MW, comparable to materials like WS2 and ZnO. These superior performances make the CsPbBr3 nanocrystal superlattices promising for applications in nonlinear devices such as optical power limiting and optical switches.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Multidisciplinary
Rivi J. Ratnaweera, Freddy A. Rodriguez Ortiz, Nicholas J. Gripp, Matthew T. Sheldon
Summary: This study investigates the dynamic alignment of colloidal CdSe/CdS nanorods in the presence of AC electric fields. The results identify two scales of interaction that lead to the field-driven optical response: the spontaneous self-assembly of the nanorods into structures with increased optical anisotropy at the mesoscale, and the macroscopic ordering of the nanorod assemblies along the direction of the applied AC field. The alignment of the nanorod ensembles improves with increasing nanorod concentration, indicating that mesoscale assembly facilitates the field-driven alignment.
Article
Chemistry, Multidisciplinary
Je-Ruei Wen, Freddy Alberto Rodriguez Ortiz, Anna Champ, Matthew T. Sheldon
Summary: This study demonstrates that the reaction kinetics of all-inorganic CsPbX3 nanocrystal growth can be significantly slowed by employing a dual injection strategy. This allows for the synthesis of highly uniform nanorods or cuboid nanocrystals with controllable size, aspect ratio, and crystal lattice structure.
Editorial Material
Optics
Yuzhe Xiao, Matthew Sheldon, Mikhail A. Kats
Summary: This article discusses how a heat-powered emitter can exceed the Planck thermal-emission limit, and argues that super-Planckian emission requires an energy distribution that is not consistent with a unique temperature.
Article
Chemistry, Physical
Jiho Kang, Zachary M. Sherman, Hannah S. N. Crory, Diana L. Conrad, Marina W. Berry, Benjamin J. Roman, Eric Anslyn, Thomas M. Truskett, Delia J. Milliron
Summary: Gelation is a powerful strategy for assembling plasmonic nanocrystal networks with customizable collective properties. Using thermoresponsive metal-terpyridine links, we demonstrate mixed nanocrystal gel networks that can rapidly assemble and disassemble with thermal cycling. By intermixing plasmonic indium oxide nanocrystals with different characteristics, we observe collective infrared absorption that deviates systematically from a linear combination of single-component gels. Our simulations reveal that these spectral deviations originate from cross-coupling between nanocrystals with distinct plasmonic properties. This thermoreversible linking strategy enables the tuning of far- and near-field optical properties in mixed nanocrystal gels.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Benjamin J. Roman, Sofia A. Shubert-Zuleta, Grant Shim, Victoria Kyveryga, Mohamed Faris, Delia J. Milliron
Summary: This study reports the dielectric sensitivity of fluorine and tin codoped indium oxide nanocubes and its dependence on their sharp faceting which gives rise to multiple plasmonic modes and on their tin-dopant concentration. It is found that the plasmon mode associated with the nanocube corners is the most sensitive and that raising dopant concentration increases dielectric sensitivity.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Sofia A. Shubert-Zuleta, Bharat Tandon, Benjamin J. Roman, Xing Yee Gan, Delia J. Milliron
Summary: In contrast to noble metal nanoparticles, doped metal oxide nanocrystals (NCs) have localized surface plasmon resonance (LSPR) in the infrared region, which can be adjusted by changing the free electron concentration through synthetic and postsynthetic doping. Quantifying electrons in NCs is crucial to understand the relationship between electron transfer processes and resulting optical changes. Both titration and LSPR peak fitting analysis are commonly used methods, but discrepancies have been observed without a clear explanation. This study examines Sn-doped In2O3 NCs with various characteristics and finds that oxidative titration consistently overestimates the number of electrons per NC due to the failure of assumed stoichiometric equivalents.
CHEMISTRY OF MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Zachary M. Sherman, Kihoon Kim, Jiho Kang, Benjamin J. Roman, Hannah S. N. Crory, Diana L. Conrad, Stephanie A. Valenzuela, Emily Lin, Manuel N. Dominguez, Stephen L. Gibbs, Eric Anslyn, Delia J. Milliron, Thomas M. Truskett
Summary: The optical properties of nanoparticle assemblies are influenced by the unique characteristics of their building blocks and spatial organization, leading to emergent phenomena. A fast, materials agnostic method has been developed to simulate the optical response of large nanoparticle assemblies with structural and compositional complexity. This method overcomes the limitations of conventional electromagnetic simulations and achieves rapid and accurate convergence for complex configurations, enabling the design of complex and hierarchically structured assemblies with desired optical characteristics.
Article
Chemistry, Physical
Freddy A. Rodriguez A. Ortiz, Boqin Zhao, Je-Ruei Wen, Ju Eun Yim, Giselle Bauer, Anna Champ, Matthew T. Sheldon
Summary: In this study, the anisotropy of the complex dielectric function of CsPbBr3 nanorods was determined by analyzing the ensemble absorption spectra and spectral fluorescence anisotropy. The results show that quantum confinement gives rise to unique axis-dependent electronic features in the dielectric function, increasing the overall fluorescence anisotropy even in the absence of quantum confinement. Additionally, this study provides a strategy for obtaining anisotropic complex dielectric functions of colloidal materials with varying composition and aspect ratios using ensemble solution-phase spectroscopy.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
News Item
Optics
Matthew Sheldon
Summary: Researchers have successfully overcome the challenge of detecting vibrations of individual molecules due to thermal noise by upconverting mid-infrared photons into visible light using nanophotonic cavities, enabling high-efficiency optical readout for single-molecule vibrational spectroscopy.
Article
Chemistry, Multidisciplinary
Noel Mireles Villegas, Josue C. Hernandez, Joshua C. John, Matthew Sheldon
Summary: We present a size-selective method for purifying and isolating perovskite CsPbBr3 nanocrystals (NCs) while preserving their surface chemistry and high photoluminescence quantum yields (PLQYs). By evaporating nonpolar co-solvents, the isolation procedure promotes the precipitation of a size-selected product. The resulting solution-phase superlattices (SLs) of NCs exhibit improved PLQYs and unique spectral absorption features, indicating the potential for achieving collective optoelectronic phenomena previously observed from solid-state assemblies.
Article
Chemistry, Physical
Benjamin J. Roman, Sofia A. Shubert-Zuleta, Grant Shim, Victoria Kyveryga, Mohamed Faris, Delia J. Milliron
Summary: We report the dielectric sensitivity of fluorine and tin codoped indium oxide nanocubes and its dependence on their sharp faceting and tin-dopant concentration. The plasmon mode associated with the nanocube corners is the most sensitive and increasing dopant concentration enhances dielectric sensitivity. Simulation results suggest that the plasmon modes associated with the edges and faces of the nanocubes are less sensitive than expected due to the presence of band bending and a resulting surface depletion layer.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
