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
Optics
Xizhen Zhang, Mengqi Lin, Lizhu Guo, Yuhang Zhang, Chuanhui Cheng, Jiashi Sun, Yi Cheng, Yongze Cao, Sai Xu, Xiangping Li, Jinsu Zhang, Baojiu Chen
Summary: Perovskite CsPbBr3 quantum dots glass is suitable for long-wavelength pass filter applications, with different preparation conditions resulting in variations in transmittance, transition wavelength, and optical density.
OPTICS AND LASER TECHNOLOGY
(2021)
Article
Chemistry, Multidisciplinary
Ghaida Alosaimi, Chien-Yu Huang, Pankaj Sharma, Tom Wu, Jan Seidel
Summary: The exceptional electronic, optoelectronic, and sensing properties of inorganic Cs-based perovskites are influenced by defect chemistry. While organic halide perovskites have been extensively studied, understanding of defect properties at grain boundaries in inorganic Cs-based perovskite quantum dots (QDs) remains limited. Scanning probe microscopy measurements of thermally treated samples reveal morphology-dependent charge carrier dynamics in CsPbBr3 QDs at the nanoscale. Defect-engineered samples show higher surface potential at grain boundaries under light illumination, indicating their role as charge collection and transport channels. The annealing process not only controls morphology but also improves optoelectrical properties and ion migration dynamics.
Article
Chemistry, Multidisciplinary
Yajing Wang, Ahui Li, Yizhen Hu, Yanping Bao, Yongfan Zhang, Xiaolin Hu, Naifeng Zhuang
Summary: By epitaxially growing a CsPbBr3 shell on the surface of CH3NH3PbBr3, CH3NH3PbBr3@CsPbBr3 quantum dots exhibit enhanced stability and strong photoluminescence, along with a high quantum yield.
CHEMICAL COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Junfeng Lu, Xiaopeng He, Juan Xu, Fangtao Li, Qingbin Tang, Xiaoxuan Wang, Jun Dai, Qiushi Yao, Feifei Qin, Chunxiang Xu
Summary: In this study, CsPbBr3 microwires were used as gain media and microresonators to achieve two-photon pumped frequency upconversion single-mode lasing. Theoretical calculation and experimental validation showed that CsPbBr3 microwires possess the capability to achieve this output, and the relationship between exciton binding energy and light emission was extracted.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Physics, Condensed Matter
Lyall Alwafi, Amlan Datta, James M. Pientka, Biplob Barman
Summary: This work investigates the photoexcitation response of CsPbBr3 Quantum Dots (QD) using two different laser wavelengths, and explores the physics behind it. The photoluminescence spectra from the sample exhibit contrasting behavior in terms of emission wavelengths and probing the phase change behavior in these material systems. The contrasting behavior is tentatively attributed to the dominant structural phase and a change in the energy band structure as the system transitions from an orthorhombic phase to a tetragonal one.
SOLID STATE COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Suman Bera, Sanjib Shyamal, Narayan Pradhan
Summary: Spiral CsPbBr3 perovskite nanorods with unique anisotropy were synthesized in this study, controlled by manipulation of alkylammonium ions composition. These nanorods were explored as photocatalysts for CO2 reduction, and it was found that the evolution of methane was dependent on the depth of the spiral nanorods. The study demonstrates that facet manipulation of complex nanorods is possible, suggesting that perovskite shapes can be constructed by design with proper reaction manipulation.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Inorganic & Nuclear
Ying Jiang, Cunxin Mei, Zhijie Zhang, Zhongliang Dong
Summary: The study successfully constructed a CsPbBr3/NCP hybrid by immobilizing CsPbBr3 nanocrystals into nanoporous carbon powder, which exhibited superior photocatalytic performance in CO2 reduction due to enhanced electron extraction and transfer, higher CO2 capturing ability, and more active sites for CO2 activation. The nanohybrid also showed remarkable reusability in photocatalytic CO2 reduction, providing a new pathway for designing high-performance photocatalysts based on perovskites for solar-energy-conversion applications.
DALTON TRANSACTIONS
(2021)
Article
Biochemical Research Methods
Xiaobing Tang, Fuqian Yang
Summary: In this study, the growth behavior of CsPbBr3 nanocrystals synthesized in a microfluidic system was analyzed by establishing the relation between bandgap and flow rate. The results showed that the size of the nanocrystals is inversely proportional to the flow rate, and increasing synthesis temperature leads to a wider size distribution.
Article
Spectroscopy
Imtiaz Ahmad, Mohammed Abohashrh, Abdur Rahim, Sadia Ahmad, Tahir Muhmood, Hongli Wen
Summary: The authors used the surface ligand crafting model to incorporate ammonia into perovskite quantum dots (PQD), and developed a solid-state sensor for ammonia detection on cellulose paper. The PQD@ZIF-8 materials showed high sensitivity and detection range for ammonia detection under ambient conditions, visible to the naked eye and a Xiaomi Note-5 mobile camera. This research provides a new platform for designing sensors with selectivity and sensitivity, and has potential for the development of fluorescent nanomaterials-based sensors for small molecule detection.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2023)
Article
Chemistry, Multidisciplinary
Chang-Min Lee, Mustafa Atabey Buyukkaya, Samuel Harper, Shahriar Aghaeimeibodi, Christopher J. K. Richardson, Edo Waks
Summary: In this study, a bright telecom-wavelength single photon source is demonstrated based on a tapered nanobeam containing InAs/InP quantum dots. The tapered nanobeam enables directional and Gaussian-like far-field emission of the quantum dots, resulting in a high-end brightness. Adopting quasi-resonant excitation helps reduce multiphoton emission and decoherence, achieving a coherence time and postselected Hong-Ou-Mandel visibility suitable for long-distance quantum networks.
Article
Chemistry, Multidisciplinary
Chaochao Qin, Zhinan Jiang, Zhongpo Zhou, Yufang Liu, Yuhai Jiang
Summary: The study on ultrafast dynamics of CsPbBr3 nanocrystals reveals that increasing excitation energy leads to longer Auger recombination lifetime but shorter hot-carriers cooling time, providing valuable insights for applications like solar cells and light-emitting devices.
Article
Engineering, Environmental
Yang Liu, Yuelei Li, Xudong Hu, Changting Wei, Bo Xu, Jing Leng, Haibo Miao, Haibo Zeng, Xiaoming Li
Summary: Surface ligands play important roles in the growth and stability of quantum dots (QDs). This study investigates the influence of dodecylbenzene sulfonic (DBSA) ligand on perovskite QDs (PQDs). The results show that DBSA-capped PQDs exhibit abnormally ripening under high-temperature conditions. A new mechanism for ion migration suppression is proposed based on internal lattice relaxation and inter-particle migration pathway elimination. However, the external quantum efficiency of the corresponding light-emitting devices is poor, which could be attributed to the unbalanced colloidal stability and film conductivity.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Physical
Atif Suhail, Ankush Saini, Shivang Beniwal, Monojit Bag
Summary: Inorganic halide perovskite nanocrystals have gained significant attention due to their enhanced stability, superior photophysical properties, and defect-tolerant nature. This study investigates the effects of precursor concentration on the structural, optical, and electronic properties of cesium lead bromide nanocrystals. It is found that as the precursor concentration decreases, the excitonic absorption band increases and the steady state photoluminescence intensity decreases. Photodetectors fabricated using different-size samples show that the photoresponsivity increases with increasing particle size. The nanocrystals synthesized from the diluted precursor solution exhibit the highest detectivity due to their larger crystal size and fewer defect states.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Inorganic & Nuclear
Tianju Chen, Qi Yang, Peng Zhang, Ruihao Chen, Yuke Lin, Weifang Zhou, Laizhi Sui, Xuan Zheng, Guoliang Chen, Feiming Li
Summary: To address the instability of colloidal cesium lead halide perovskite nanocrystals (CsPbX3 PNCs), a stapled ligand called perfluoroglutaric acid (PFGA) is proposed to effectively passivate the surface of CsPbBr3 PNCs. The PFGA-capped CsPbBr3 PNCs exhibit high photoluminescence quantum yield, outstanding dispersion in polar solvents, and excellent stability after rigorous washing and long-term storage. These findings provide insight into surface engineering strategies for producing highly emissive and stable PNCs and broadening their sensing applications in polar media.
INORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Optics
Vojtech Miller, Karel Zidek
Summary: This paper presents a setup for high-precision transmission measurement of Ti:Sa crystals using Nd:YAG and Er:YAG lasers. By utilizing synchronous detection via a double integrated sphere, the transmission uncertainty of 0.01-0.03% and FoM precision of +/- 7.5% were achieved. Experimental results demonstrate that spatial inhomogeneities and angular mismatch can significantly affect the FoM values.
Article
Chemistry, Physical
Supriya Ghosh, Bapi Pradhan, Weihua Lin, Yiyue Zhang, Luca Leoncino, Pavel Chabera, Kaibo Zheng, Eduardo Solano, Johan Hofkens, Tonu Pullerits
Summary: In the past two decades, research has focused on suppressing Auger recombination in metal-chalcogenide and perovskite nanocrystals (PNCs) for photovoltaic and light emitting device (LED) applications. A study examined dodecahedron cesium lead bromide perovskite nanocrystals (DNCs) and found that they exhibit slower Auger recombination compared to hexahedron nanocrystals (HNCs). The research demonstrates that multiexciton recombinations result in lower Auger recombination rates in DNCs than in HNCs.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Optics
Jiri Junek, Karel Zidek
Summary: The RATS method is proven to be useful for measuring photoluminescence dynamics and fluorescence lifetime imaging. Two fundamental developments are presented: using random digital laser modulation for nanosecond-resolution measurement of photoluminescence dynamics, and using a single-pixel camera experiment for alternative evaluation of fluorescence lifetime imaging. These developments significantly save post-processing time and improve the accuracy stability of FLIM spectrogram.
Article
Optics
Marek Mach, Pavel Psota, Karel Zidek, Pavel Mokry
Summary: A compact lensless method based on digital holographic Fizeau interferometer is developed to image domain patterns in ferroelectric single crystals, providing a large field-of-view image with high spatial resolution. The method utilizes the electro-optic phenomenon to display the domain patterns in the crystal and measure the difference in the index of refraction.
Article
Chemistry, Physical
Albin Hedse, Alex Arash Sand Kalaee, Andreas Wacker, Tonu Pullerits
Summary: The double quantum coherence (DQC) signal in nonlinear spectroscopy provides information about many-body correlation effects that are difficult to obtain through other methods. Contrary to intuition, pulse overlap-related artifacts are not filtered out by the Fourier transform. Careful analysis of experiments is necessary to account for the pulse-overlap artifact.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Daniel Finkelstein-Shapiro, Pierre-Adrien Mante, Sinan Balci, Donatas Zigmantas, Tonu Pullerits
Summary: In polaritons, the properties of matter are modified by mixing molecular transitions with light modes, leading to hybrid light-matter states and modified exciton dynamics. This article rigorously derives non-Hermitian Hamiltonians in the response function formalism of nonlinear spectroscopy and explores spectroscopic signatures of plexcitons. The study reveals interference and Rabi splitting in linear spectroscopy and a qualitative change in the symmetry of the line shape of the nonlinear signal when crossing the exceptional point.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Xinyue Wang, Hongxiang Wang, Meixia Zhang, Tonu Pullerits, Peng Song
Summary: By studying the photoinduced electron transfer properties of the D-D-A molecule ((TPA-TT)-BODIPY-C60) in an external electric field (Fext), the excited-state properties of the molecule and the charge-transfer processes were investigated. The electronic coupling (VDA), reorganization energy (lambda), and free energy (Delta G) were calculated and simulated. It was found that exciton dissociation occurs in the Marcus inverted region and the charge-transfer rate is influenced by the changes in VDA and Delta G. The results provide a method for the design of a new type of electron transfer process with high efficiency in the D-D-A system.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Multidisciplinary
Vanessa Ruck, Mikkel B. Liisberg, Christian Brinch Mollerup, Yanmei He, Junsheng Chen, Cecilia Cerretani, Tom Vosch
Summary: This article presents a DNA-stabilized silver nanocluster (DNA-AgNC) with dual emission in the red and near-infrared regions. Mass spectrometry data shows that two DNA strands stabilize 18 silver atoms with a nanocluster charge of 12+. Steady-state and time-resolved methods were used to characterize the red fluorescence and NIR luminescence, and the luminescence-to-fluorescence ratio was found to be excitation-intensity-dependent, making it a nanoscale excitation intensity probe.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Engineering, Environmental
Hong Yin, Wenzhi Li, Zhongyi Wang, Pengyuan Wang, Xin Xu, Peigeng Han, Xin Mao, Feng Liu, Keli Han, Junsheng Chen, Ruiling Zhang
Summary: In this study, luminescent low-dimensional organic copper halides were developed by introducing three different cations with increasing steric hindrance: 1D ETMACu2I3, 1D TEACu2I3, and 0D TBMACuI2. The dimensionality of the prepared copper halides decreased with the increase of the steric hindrance of the organic cations, while the photoluminescence spectra became broader. Of note, 0D TBMACuI2 emitted bright warm white light with dual emission bands. The mechanism of the unique dual emission was unveiled through systematic spectroscopic study.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Physical
Yanmei He, Siping Liu, Zehan Yao, Qian Zhao, Pavel Chabera, Kaibo Zheng, Bin Yang, Tonu Pullerits, Junsheng Chen
Summary: Low-dimensional perovskite-inspired materials with self-trapped exciton (STE) emission have sparked cutting-edge research in optoelectronics. However, there has been little focus on the intrinsic dynamics of broad emission based on STE in these materials. In this study, through femtosecond transient absorption spectroscopy, we directly observed the ultrafast process of STE formation in Cs2ZrCl6 nanocrystals, and obtained the dynamic rules of ultrafast STE formation. The formed STEs relax to an intermediate STE state with a lifetime of approximately 180 ps before reaching the emissive STE state with a lifetime of about 15 μs. Our work provides a comprehensive and precise dynamic picture of STE emission in low-dimensional metal halides and sheds light on expanding their potential applications.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Physical
Tianyi Hu, Michael S. S. Seifner, Markus Snellman, Daniel Jacobsson, Mehran Sedrpooshan, Pau Ternero, Maria E. Messing, Kimberly A. A. Dick
Summary: In the last few decades, the metal-assisted growth approach has shown potential in controlling the crystal properties of semiconductor nanowires. Recent studies have successfully grown semiconductor nanowires using multiphase seed particles. Exploring alternative metal seeds and understanding the mechanisms for growing semiconductor nanowires can improve the control over the crystal growth process.
Article
Chemistry, Physical
Xin Mao, Zhongyi Wang, Fen Zhang, Hong Yin, Xin Xu, Junsheng Chen, Zhen Chen, Junhua Luo, Keli Han, Ruiling Zhang
Summary: In this study, high-quality Sb3+-doped 0D Rb2ScCl5(H2O) perovskite single crystals were synthesized and their photophysical properties were investigated. The introduction of Sb3+ dramatically enhanced the emission quantum yield from less than 1% to about 53%. Spectroscopic characterizations revealed that the enhancement was attributed to efficient energy transfer from Sb3+ to the emissive self-trapped excitons (STE). Moreover, 0.2%Sb3+:Rb2ScCl5(H2O) single crystals showed potential applications in direct X-ray detection with a high sensitivity of 58.5 mu C Gy(-1) cm(-2).
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Review
Materials Science, Multidisciplinary
Pengfei Cheng, Keli Han, Junsheng Chen
Summary: Metal halide perovskites, with their excellent photophysical properties, have attracted extensive attention in the field of photocatalysis. However, the toxicity and instability issues of conventional lead-based perovskites limit their application prospects. The rapid development of lead-free halide perovskites (LFHPs) provides new opportunities for photocatalysis. This Review summarizes the recent progresses of LFHPs for photocatalytic applications and discusses strategies to improve their performance and stability.
ACS MATERIALS LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Mehran Sedrpooshan, Claudiu Bulbucan, Pau Ternero, Pierfrancesco Maltoni, Calle Preger, Simone Finizio, Benjamin Watts, Davide Peddis, Adam M. Burke, Maria E. Messing, Rasmus Westerstrom
Summary: In this paper, a template-free technique is proposed to produce 1D magnetic nanochains and nanowires directly on substrates and device architectures through the directed self-assembly of gas-phase-generated nanoparticles. It is found that the orientation of the nanochains and the presence of multi-domain particles play a key role in domain formation and magnetization reversal, while the improved magnetic properties of the nanowires can be attributed to the uniform formation of magnetocrystalline anisotropy and the onset of exchange interactions.
Article
Chemistry, Physical
Li Zhao, Xuehui Geng, Guoxia Han, Yahui Guo, Runze Liu, Junsheng Chen
Summary: This study investigates the excited state decay mechanism of cytidine in both gas phase and aqueous solution using high-level electronic structure calculations and non-adiabatic dynamic simulations. It is found that cytidine undergoes barrierless decay driven by ring-puckering motion and relaxation channel with a small energy barrier driven by elongation motion of C=O bond. The presence of water molecules significantly reduces the energy barrier, suggesting that the long-lived decay channel in aqueous solution is likely attributed to the cytidine-water intermolecular hydrogen/proton transfer process. These findings contribute to a better understanding of the photostability of DNAs and RNAs and resolve the debate on the cytidine excited-state decay mechanism.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
