1
|
Abstract
Nonlinear optical (NLO) microscopy relies on multiple light-matter interactions to provide unique contrast mechanisms and imaging capabilities that are inaccessible to traditional linear optical imaging approaches, making them versatile tools to understand a wide range of complex systems. However, the strong excitation fields that are necessary to drive higher-order optical processes efficiently are often responsible for photobleaching, photodegradation, and interruption in many systems of interest. This is especially true for imaging living biological samples over prolonged periods of time or in accessing intrinsic dynamics of electronic excited-state processes in spatially heterogeneous materials. This perspective outlines some of the key limitations of two NLO imaging modalities implemented in our lab and highlights the unique potential afforded by the quantum properties of light, especially entangled two-photon absorption based NLO spectroscopy and microscopy. We further review some of the recent exciting advances in this emerging filed and highlight some major challenges facing the realization of quantum-light-enabled NLO imaging modalities.
Collapse
Affiliation(s)
- Ying-Zhong Ma
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Benjamin Doughty
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| |
Collapse
|
2
|
Blake MJ, Colon BA, Calhoun TR. Leaving the Limits of Linearity for Light Microscopy. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2020; 124:24555-24565. [PMID: 34306294 PMCID: PMC8301257 DOI: 10.1021/acs.jpcc.0c07501] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Nonlinear microscopy has enabled additional modalities for chemical contrast, deep penetration into biological tissues, and the ability to collect dynamics on ultrafast timescales across heterogenous samples. The additional light fields introduced to a sample offer seemingly endless possibilities for variation to optimize and customize experimentation and the extraction of physical insight. This perspective highlights three areas of growth in this diverse field: the collection of information across multiple timescales, the selective imaging of interfacial chemistry, and the exploitation of quantum behavior for future imaging directions. Future innovations will leverage the work of the studies reviewed here as well as address the current challenges presented.
Collapse
Affiliation(s)
- Marea J Blake
- Department of Chemistry, University of Tennessee, Knoxville, TN 37996
| | - Brandon A Colon
- Department of Chemistry, University of Tennessee, Knoxville, TN 37996
| | - Tessa R Calhoun
- Department of Chemistry, University of Tennessee, Knoxville, TN 37996
| |
Collapse
|
3
|
Shi R, Vasenko AS, Long R, Prezhdo OV. Edge Influence on Charge Carrier Localization and Lifetime in CH 3NH 3PbBr 3 Perovskite: Ab Initio Quantum Dynamics Simulation. J Phys Chem Lett 2020; 11:9100-9109. [PMID: 33048554 DOI: 10.1021/acs.jpclett.0c02800] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The distribution of charge carriers in metal halide perovskites draws strong interest from the solar cell community, with experiments demonstrating that edges of various microstructures can improve material performance. This is rather surprising because edges and grain boundaries are often viewed as the main source of charge traps. We demonstrate by ab initio quantum dynamics simulations that edges of the CH3NH3PbBr3 perovskite create shallow trap states that mix well with the valence and conduction bands of the bulk and therefore support mobile charge carriers. Charges are steered to the edges energetically, facilitating dissociation of photo-generated excitons into free carriers. The edge-driven charge separation extends carrier lifetimes because of decreased overlap of the electron and hole wave functions, which leads to reduction of the nonadiabatic coupling responsible for nonradiative electron-hole recombination. Reduction of spatial symmetry near the edges activates additional vibrational modes that accelerate coherence loss within the electronic subsystem, further extending carrier lifetimes. Enhanced atomic motions at edges increase fluctuations of edge energy levels, enhancing mixing with band states and improving charge mobility. The simulations contribute to the atomistic understanding of the unusual properties of metal halide perovskites, generating the fundamental knowledge needed to design high-performance optoelectronic devices.
Collapse
Affiliation(s)
- Ran Shi
- College of Chemistry, Key Laboratory of Theoretical & Computational Photochemistry of Ministry of Education, Beijing Normal University, Beijing 100875, People's Republic of China
| | - Andrey S Vasenko
- National Research University Higher School of Economics, 101000 Moscow, Russia
- I.E. Tamm Department of Theoretical Physics, P.N. Lebedev Physical Institute, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Run Long
- College of Chemistry, Key Laboratory of Theoretical & Computational Photochemistry of Ministry of Education, Beijing Normal University, Beijing 100875, People's Republic of China
| | - Oleg V Prezhdo
- Departments of Chemistry, and Physics and Astronomy, University of Southern California, Los Angeles, California 90089, United States
| |
Collapse
|
4
|
Fathi A, Jokar E, Lee Y, Diau EW. A Direct Mapping Approach to Understand Carrier Relaxation Dynamics in Varied Regions of a Polycrystalline Perovskite Film. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202008305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Amir Fathi
- Department of Applied Chemistry and Institute of Molecular Science National Chiao Tung University 1001 Ta-Hsueh Rd. Hsinchu 30010 Taiwan
| | - Efat Jokar
- Center for Emergent Functional Matter Science National Chiao Tung University 1001 Ta-Hsueh Rd. Hsinchu 30010 Taiwan
| | - Yuan‐Pern Lee
- Department of Applied Chemistry and Institute of Molecular Science National Chiao Tung University 1001 Ta-Hsueh Rd. Hsinchu 30010 Taiwan
- Center for Emergent Functional Matter Science National Chiao Tung University 1001 Ta-Hsueh Rd. Hsinchu 30010 Taiwan
| | - Eric Wei‐Guang Diau
- Department of Applied Chemistry and Institute of Molecular Science National Chiao Tung University 1001 Ta-Hsueh Rd. Hsinchu 30010 Taiwan
- Center for Emergent Functional Matter Science National Chiao Tung University 1001 Ta-Hsueh Rd. Hsinchu 30010 Taiwan
| |
Collapse
|
5
|
Fathi A, Jokar E, Lee YP, Diau EWG. A Direct Mapping Approach to Understand Carrier Relaxation Dynamics in Varied Regions of a Polycrystalline Perovskite Film. Angew Chem Int Ed Engl 2020; 59:19001-19005. [PMID: 32681616 DOI: 10.1002/anie.202008305] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Indexed: 11/11/2022]
Abstract
We developed a direct mapping approach to overlay the image of a polycrystalline perovskite film obtained from the transient absorption microscope (TAM) with that from the scanning electron microscope (SEM). By mapping these imaging data pixel by pixel, we are able to observe the relaxation dynamics of the photo-generated charge carriers on varied regions of the film. The carrier relaxation dynamics contain a dominated single-exponential decay component owing to the recombination of charge carriers. The lifetime distribution of charge recombination shows a bimodal feature, for which the rapid and slow distributions are assigned as free and trapped carriers, respectively. The charge recombination was slower in the grain boundary (GB) region than in the grain interior (GI) region. The small grains have longer lifetimes than the large grains for the crystal size smaller than 500 nm. Therefore, GB with retarded charge recombination might play a positive role in a perovskite solar cell.
Collapse
Affiliation(s)
- Amir Fathi
- Department of Applied Chemistry and Institute of Molecular Science, National Chiao Tung University, 1001 Ta-Hsueh Rd., Hsinchu, 30010, Taiwan
| | - Efat Jokar
- Center for Emergent Functional Matter Science, National Chiao Tung University, 1001 Ta-Hsueh Rd., Hsinchu, 30010, Taiwan
| | - Yuan-Pern Lee
- Department of Applied Chemistry and Institute of Molecular Science, National Chiao Tung University, 1001 Ta-Hsueh Rd., Hsinchu, 30010, Taiwan.,Center for Emergent Functional Matter Science, National Chiao Tung University, 1001 Ta-Hsueh Rd., Hsinchu, 30010, Taiwan
| | - Eric Wei-Guang Diau
- Department of Applied Chemistry and Institute of Molecular Science, National Chiao Tung University, 1001 Ta-Hsueh Rd., Hsinchu, 30010, Taiwan.,Center for Emergent Functional Matter Science, National Chiao Tung University, 1001 Ta-Hsueh Rd., Hsinchu, 30010, Taiwan
| |
Collapse
|
6
|
Contrasting Electron and Hole Transfer Dynamics from CH(NH2)2PbI3 Perovskite Quantum Dots to Charge Transport Layers. APPLIED SCIENCES-BASEL 2020. [DOI: 10.3390/app10165553] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In this work, the ultrafast transient absorption spectroscopy (TAs) was utilized to first investigate the charge transfer from the emerging FAPbI3 (FA = CH(NH2)2) perovskite quantum dots (PQDs) to charge transport layers. Specifically, we compared the TAs in pure FAPbI3 PQDs, PQDs grown with both electron and hole transfer layers (ETL and HTL), and PQDs with only ETL or HTL. The TA signals induced by photoexcited electrons decay much faster in PQDs samples with the ETL (~20 ps) compared to the pure FAPbI3 PQDs (>1 ns). These results reveal that electrons can effectively transport between coupled PQDs and transfer to the ETL (TiO2) at a time scale of 20 ps, much faster than the bimolecular charge recombination inside the PQDs (>1 ns), and the electron transfer efficiency is estimated to be close to 100%. In contrast, the temporal evolution of the TA signals in the PQDs with and without HTL exhibit negligible change, and no substantive hole transfer to the HTL (poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine], PTAA) occurs within 1 ns. The much slower hole transfer implies the further potential of increasing the overall photo-carrier conversion efficiency through enhancing the hole diffusion length and fine-tuning the coupling between the HTL and PQDs.
Collapse
|
7
|
Colon BA, Hassan MR, Saleheen A, Baker CA, Calhoun TR. Total Internal Reflection Transient Absorption Microscopy: An Online Detection Method for Microfluidics. J Phys Chem A 2020; 124:4160-4170. [PMID: 32338897 DOI: 10.1021/acs.jpca.9b12046] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Microreactors have garnered widespread attention for their tunability and precise control of synthetic parameters to efficiently produce target species. Despite associated advances, a lack of online detection and optimization methods has stalled the progression of microfluidic reactors. Here we employ and characterize a total internal reflection transient absorption microscopy (TIRTAM) instrument to image excited state dynamics on a continuous flow device. The experiments presented demonstrate the capability to discriminate between different chromophores as well as in differentiating the effects of local chemical environments that a chromophore experiences. This work presents the first such online transient absorption measurements and provides a new direction for the advancement and optimization of chemical reactions in microfluidic devices.
Collapse
Affiliation(s)
- Brandon A Colon
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Muhammad Redwan Hassan
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Amirus Saleheen
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Christopher A Baker
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Tessa R Calhoun
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| |
Collapse
|
8
|
Doughty B, Simpson MJ, Das S, Xiao K, Ma YZ. Connecting Femtosecond Transient Absorption Microscopy with Spatially Coregistered Time Averaged Optical Imaging Modalities. J Phys Chem A 2020; 124:3915-3923. [PMID: 32309940 DOI: 10.1021/acs.jpca.9b11996] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Multimodal all-optical imaging involving coregistered femtosecond transient absorption microscopy (TAM), time-integrated photoluminescence (PL), and steady-state modalities such as confocal reflectance and transmission offers an appealing approach to gain a comprehensive understanding of complex electronic excited-state phenomena in spatially heterogeneous systems. A unique combination of these modalities allows us to unravel not only the competing electronic excited-state dynamical processes but also the underlying morphological information with simultaneous high temporal and spatial resolution. However, correlating the various images obtained from time-resolved and time-independent modalities is generally nontrivial and particularly challenging when the electronic dynamics under study evolve in both time and space. Here, we demonstrate a new approach for rationally correlating time-resolved microscopy with coregistered time-integrated or steady-state modalities. Specifically, our approach involves an extended global lifetime analysis of the time-resolved microscopic data set to separate distinct dynamical processes taking place on commensurate time scales, and the resulting decay-associated amplitude maps (DAAMs) were applied to explore correlations with the images acquired using time-independent modalities. The feasibility of our approach was validated through analyzing a multimodal data set acquired from a thin film of chloride-containing mixed lead halide perovskites (CH3NH3PbI3-xClx) using femtosecond transient absorption, time-integrated PL, and confocal reflectance microscopies. Analysis of the results obtained enable us to gain new insight into the complex ultrafast relaxation dynamics in this highly heterogeneous system.
Collapse
Affiliation(s)
- Benjamin Doughty
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Mary Jane Simpson
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Sanjib Das
- Department of Electrical Engineering and Computer Science, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Kai Xiao
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Ying-Zhong Ma
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| |
Collapse
|
9
|
Zhu Y, Cheng JX. Transient absorption microscopy: Technological innovations and applications in materials science and life science. J Chem Phys 2020; 152:020901. [PMID: 31941290 PMCID: PMC7195865 DOI: 10.1063/1.5129123] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 12/15/2019] [Indexed: 01/08/2023] Open
Abstract
Transient absorption (TA) spectroscopy has been extensively used in the study of excited state dynamics of various materials and molecules. The transition from TA spectroscopy to TA microscopy, which enables the space-resolved measurement of TA, is opening new investigations toward a more complete picture of excited state dynamics in functional materials, as well as the mapping of crucial biopigments for precision diagnosis. Here, we review the recent instrumental advancement that is pushing the limit of spatial resolution, detection sensitivity, and imaging speed. We further highlight the emerging application in materials science and life science.
Collapse
Affiliation(s)
- Yifan Zhu
- Department of Chemistry, Boston University, Boston, Massachusetts 02215, USA
| | - Ji-Xin Cheng
- Department of Chemistry, Boston University, Boston, Massachusetts 02215, USA
| |
Collapse
|
10
|
Jiang Y, Wang X, Pan A. Properties of Excitons and Photogenerated Charge Carriers in Metal Halide Perovskites. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2019; 31:e1806671. [PMID: 31106917 DOI: 10.1002/adma.201806671] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Revised: 03/01/2019] [Indexed: 05/25/2023]
Abstract
Metal halide perovskites (MHPs) have recently attracted great attention from the scientific community due to their excellent photovoltaic performance as well as their tremendous potential for other optoelectronic applications such as light-emitting diodes, lasers, and photodetectors. Despite the rapid progress in device applications, a solid understanding of the photophysical properties behind the device performance is highly desirable for MHPs. Here, the properties of excitons and photogenerated charge carriers in MHPs are explored. The unique dielectric constant properties, crystal-liquid duality, and fundamental optical processes of MHPs are first discussed. The properties of excitons and related phenomena in MHPs are then detailed, including the exciton binding energy determined by various methods and their influence factors, exciton dynamics, exciton-photon coupling and related applications, and exciton-phonon coupling in MHPs. The properties of photogenerated free charge carriers in MHPs such as the carrier diffusion length, mobility, and recombination are described. Recent progress in various applications is also demonstrated. Finally, a conclusion and perspectives of future studies for MHPs are presented.
Collapse
Affiliation(s)
- Ying Jiang
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, School of Physics and Electronics, Hunan University, Changsha, 410012, China
| | - Xiao Wang
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, School of Physics and Electronics, Hunan University, Changsha, 410012, China
| | - Anlian Pan
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, College of Materials Science and Engineering, Hunan University, Changsha, 410012, China
| |
Collapse
|
11
|
Grumstrup EM. Spatiotemporal coupling of excited state dynamics in time-resolved microscopies. OPTICS EXPRESS 2019; 27:31385-31393. [PMID: 31684373 DOI: 10.1364/oe.27.031385] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Accepted: 10/01/2019] [Indexed: 06/10/2023]
Abstract
In the high-density excitation limit, as is often probed with ultrafast spectroscopies, spatial and temporal evolution of photogenerated excited states are strongly coupled, giving rise to artifacts that influence experimentally-determined material parameters. The interplay between spatial and temporal degrees of freedom is especially pronounced in pump-probe microscopy, where small laser spot sizes amplify the effects of spatiotemporal coupling on spectroscopic observables. To quantitatively model these effects, a continuum model is developed that accounts for laser spot size as well as nonlinear excited state decay and diffusion. It is shown that effective excitation densities cannot be used to determine quantitatively correct rate constants. Significant error is introduced unless experimental data is fit with a numerical model that accounts for spatial anisotropy in the excitation density. Furthermore, the quantitative determination of material diffusion coefficients is shown to be highly sensitive to experimental parameters.
Collapse
|
12
|
Denk O, Zheng K, Zigmantas D, Žídek K. Compressive imaging of transient absorption dynamics on the femtosecond timescale. OPTICS EXPRESS 2019; 27:10234-10246. [PMID: 31045167 DOI: 10.1364/oe.27.010234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 03/02/2019] [Indexed: 06/09/2023]
Abstract
Femtosecond spectroscopy is an important tool used for tracking rapid photoinduced processes in a variety of materials. To spatially map the processes in a sample would substantially expand the method's capabilities. This is, however, difficult to achieve, due to the necessity of using low-noise detection and maintaining feasible data acquisition time. Here, we demonstrate realization of an imaging pump-probe setup, featuring sub-100 fs temporal resolution, by using a straightforward modification of a standard pump-probe technique, which uses a randomly structured probe beam. The structured beam, made by a diffuser, enabled us to computationally reconstruct the maps of transient absorption dynamics based on the concept of compressed sensing. We demonstrate the setup's functionality in two proof-of-principle experiments, where we achieve spatial resolution of 20 μm. The presented concept provides a feasible route to imaging, by using the pump-probe technique and ultrafast spectroscopy in general.
Collapse
|
13
|
Beane G, Devkota T, Brown BS, Hartland GV. Ultrafast measurements of the dynamics of single nanostructures: a review. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2019; 82:016401. [PMID: 30485256 DOI: 10.1088/1361-6633/aaea4b] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The ability to study single particles has revolutionized nanoscience. The advantage of single particle spectroscopy measurements compared to conventional ensemble studies is that they remove averaging effects from the different sizes and shapes that are present in the samples. In time-resolved experiments this is important for unraveling homogeneous and inhomogeneous broadening effects in lifetime measurements. In this report, recent progress in the development of ultrafast time-resolved spectroscopic techniques for interrogating single nanostructures will be discussed. The techniques include far-field experiments that utilize high numerical aperture (NA) microscope objectives, near-field scanning optical microscopy (NSOM) measurements, ultrafast electron microscopy (UEM), and time-resolved x-ray diffraction experiments. Examples will be given of the application of these techniques to studying energy relaxation processes in nanoparticles, and the motion of plasmons, excitons and/or charge carriers in different types of nanostructures.
Collapse
Affiliation(s)
- Gary Beane
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, United States of America
| | | | | | | |
Collapse
|
14
|
Belianinov A, Ievlev AV, Lorenz M, Borodinov N, Doughty B, Kalinin SV, Fernández FM, Ovchinnikova OS. Correlated Materials Characterization via Multimodal Chemical and Functional Imaging. ACS NANO 2018; 12:11798-11818. [PMID: 30422627 PMCID: PMC9850281 DOI: 10.1021/acsnano.8b07292] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Multimodal chemical imaging simultaneously offers high-resolution chemical and physical information with nanoscale and, in select cases, atomic resolution. By coupling modalities that collect physical and chemical information, we can address scientific problems in biological systems, battery and fuel cell research, catalysis, pharmaceuticals, photovoltaics, medicine, and many others. The combined systems enable the local correlation of material properties with chemical makeup, making fundamental questions of how chemistry and structure drive functionality approachable. In this Review, we present recent progress and offer a perspective for chemical imaging used to characterize a variety of samples by a number of platforms. Specifically, we present cases of infrared and Raman spectroscopies combined with scanning probe microscopy; optical microscopy and mass spectrometry; nonlinear optical microscopy; and, finally, ion, electron, and probe microscopies with mass spectrometry. We also discuss the challenges associated with the use of data originated by the combinatorial hardware, analysis, and machine learning as well as processing tools necessary for the interpretation of multidimensional data acquired from multimodal studies.
Collapse
Affiliation(s)
- Alex Belianinov
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Institute for Functional Imaging of Materials, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Anton V. Ievlev
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Institute for Functional Imaging of Materials, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Matthias Lorenz
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Institute for Functional Imaging of Materials, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Nikolay Borodinov
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Institute for Functional Imaging of Materials, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Benjamin Doughty
- Chemical Science Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Sergei V. Kalinin
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Institute for Functional Imaging of Materials, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Facundo M. Fernández
- School of Chemistry and Biochemistry, Georgia Institute of Technology and Petit Institute for Biochemistry and Bioscience, Atlanta, Georgia 30332, United States
| | - Olga S. Ovchinnikova
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Institute for Functional Imaging of Materials, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Corresponding Author:
| |
Collapse
|
15
|
Yang B, Chen J, Shi Q, Wang Z, Gerhard M, Dobrovolsky A, Scheblykin IG, Karki KJ, Han K, Pullerits T. High Resolution Mapping of Two-Photon Excited Photocurrent in Perovskite Microplate Photodetector. J Phys Chem Lett 2018; 9:5017-5022. [PMID: 30124049 DOI: 10.1021/acs.jpclett.8b02250] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We fabricate photodetectors based on solution-processed single CH3NH3PbBr3 microcrystals (MCs) and map the two-photon absorption (TPA) excited photocurrent (PC) with spatial resolution of 1 μm. We find that the charge carrier transport length in the MCs depends on the applied electric field, and increases from 5.7 μm for 0.02 V bias (dominated by carrier diffusion) to 23.2 μm for 2 V bias (dominated by carrier drift). Furthermore, PC shows strong spatial variations. Combining the PC mapping results with time-resolved photoluminescence microscopy, we demonstrate that the spatial distribution of PC mainly originates from the inhomogeneous distribution of trap-states across perovskite MCs. This suggests that there is still large margin for improvement of perovskite single crystal devices by better controlling of the traps.
Collapse
Affiliation(s)
- Bin Yang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics (DICP) , Chinese Academy of Sciences , 457 Zhongshan Road , Dalian , Liaoning 116023 , China
- University of the Chinese Academy of Sciences , Beijing 100039 , P. R. China
| | - Junsheng Chen
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics (DICP) , Chinese Academy of Sciences , 457 Zhongshan Road , Dalian , Liaoning 116023 , China
- Department of Chemical Physics and NanoLund, Chemical Center , Lund University , P.O. Box 124, 22100 Lund , Sweden
| | - Qi Shi
- Department of Chemical Physics and NanoLund, Chemical Center , Lund University , P.O. Box 124, 22100 Lund , Sweden
| | - Zhengjun Wang
- Department of Chemical Physics and NanoLund, Chemical Center , Lund University , P.O. Box 124, 22100 Lund , Sweden
| | - Marina Gerhard
- Department of Chemical Physics and NanoLund, Chemical Center , Lund University , P.O. Box 124, 22100 Lund , Sweden
| | - Alexander Dobrovolsky
- Department of Chemical Physics and NanoLund, Chemical Center , Lund University , P.O. Box 124, 22100 Lund , Sweden
| | - Ivan G Scheblykin
- Department of Chemical Physics and NanoLund, Chemical Center , Lund University , P.O. Box 124, 22100 Lund , Sweden
| | - Khadga Jung Karki
- Department of Chemical Physics and NanoLund, Chemical Center , Lund University , P.O. Box 124, 22100 Lund , Sweden
| | - Keli Han
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics (DICP) , Chinese Academy of Sciences , 457 Zhongshan Road , Dalian , Liaoning 116023 , China
| | - Tõnu Pullerits
- Department of Chemical Physics and NanoLund, Chemical Center , Lund University , P.O. Box 124, 22100 Lund , Sweden
| |
Collapse
|
16
|
Higgins K, Calhoun TR. Compressed supercontinuum probe for transient absorption microscopy. OPTICS LETTERS 2018; 43:1750-1753. [PMID: 29652356 PMCID: PMC6342203 DOI: 10.1364/ol.43.001750] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Accepted: 03/10/2018] [Indexed: 05/06/2023]
Abstract
Here, we combine three optical advancements to transient absorption microscopy in order to access the photodynamics in systems requiring stringent spatial and temporal resolution criteria. First, a broadband visible probe is generated by a commercial photonic crystal fiber. Second, a spatial light modulator-based pulse shaper is incorporated to reduce the pulse dispersion and improve temporal resolution. Third, 1.4 numerical aperture objectives for excitation and light collection provide optimal spatial resolution. The result of these improvements is a probe beam that spans 115 nm across the visible region yet maintains a ∼100 fs instrument response at the sample position. We demonstrate the capabilities of this microscope by imaging polystyrene beads in a solution of IR-144 dye, revealing aggregated species at the bead surfaces.
Collapse
Affiliation(s)
- Kevin Higgins
- Department of Chemistry, University of Tennessee, Knoxville. 1420 Circle Dr., Knoxville TN 37996
| | - Tessa R. Calhoun
- Department of Chemistry, University of Tennessee, Knoxville. 1420 Circle Dr., Knoxville TN 37996
| |
Collapse
|
17
|
Dar MI, Franckevičius M, Arora N, Redeckas K, Vengris M, Gulbinas V, Zakeeruddin SM, Grätzel M. High photovoltage in perovskite solar cells: New physical insights from the ultrafast transient absorption spectroscopy. Chem Phys Lett 2017. [DOI: 10.1016/j.cplett.2017.04.046] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
18
|
Simpson MJ, Doughty B, Das S, Xiao K, Ma YZ. Separating Bulk and Surface Contributions to Electronic Excited-State Processes in Hybrid Mixed Perovskite Thin Films via Multimodal All-Optical Imaging. J Phys Chem Lett 2017; 8:3299-3305. [PMID: 28675298 DOI: 10.1021/acs.jpclett.7b01368] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A comprehensive understanding of electronic excited-state phenomena underlying the impressive performance of solution-processed hybrid halide perovskite solar cells requires access to both spatially resolved electronic processes and corresponding sample morphological characteristics. Here, we demonstrate an all-optical multimodal imaging approach that enables us to obtain both electronic excited-state and morphological information on a single optical microscope platform with simultaneous high temporal and spatial resolution. Specifically, images were acquired for the same region of interest in thin films of chloride containing mixed lead halide perovskites (CH3NH3PbI3-xClx) using femtosecond transient absorption, time-integrated photoluminescence, confocal reflectance, and transmission microscopies. Comprehensive image analysis revealed the presence of surface- and bulk-dominated contributions to the various images, which describe either spatially dependent electronic excited-state properties or morphological variations across the probed region of the thin films. These results show that PL probes effectively the species near or at the film surface.
Collapse
Affiliation(s)
- Mary Jane Simpson
- Chemical Sciences Division, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States
| | - Benjamin Doughty
- Chemical Sciences Division, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States
| | - Sanjib Das
- Department of Electrical Engineering and Computer Science, University of Tennessee , Knoxville, Tennessee 37996, United States
| | - Kai Xiao
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States
| | - Ying-Zhong Ma
- Chemical Sciences Division, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States
| |
Collapse
|
19
|
Han Q, Wu W, Liu W, Yang Y. The peak shift and evolution of upconversion luminescence from CsPbBr3nanocrystals under femtosecond laser excitation. RSC Adv 2017. [DOI: 10.1039/c7ra06211g] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Compared with normal PL, a red shift of upconversion PL spectrum is observed. Time-resolved PL and TA spectroscopies show FWHM and peak position are changed at various times, which suggest the existence of more than single excited state.
Collapse
Affiliation(s)
- Qiuju Han
- Department of Physics
- Harbin Institute of Technology
- Harbin
- China
- School of Science
| | - Wenzhi Wu
- School of Electronic Engineering
- Heilongjiang University
- Harbin
- China
| | - Weilong Liu
- Department of Physics
- Harbin Institute of Technology
- Harbin
- China
| | - Yanqiang Yang
- Department of Physics
- Harbin Institute of Technology
- Harbin
- China
| |
Collapse
|
20
|
Osherov A, Hutter EM, Galkowski K, Brenes R, Maude DK, Nicholas RJ, Plochocka P, Bulović V, Savenije TJ, Stranks SD. The Impact of Phase Retention on the Structural and Optoelectronic Properties of Metal Halide Perovskites. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2016; 28:10757-10763. [PMID: 27757994 DOI: 10.1002/adma.201604019] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Revised: 09/10/2016] [Indexed: 06/06/2023]
Abstract
The extent to which the soft structural properties of metal halide perovskites affect their optoelectronic properties is unclear. X-ray diffraction and micro-photoluminescence measurements are used to show that there is a coexistence of both tetragonal and orthorhombic phases through the low-temperature phase transition, and that cycling through this transition can lead to structural changes and enhanced optoelectronic properties.
Collapse
Affiliation(s)
- Anna Osherov
- Research Laboratory of Electronics, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA
| | - Eline M Hutter
- Opto-electronic Materials Section, Department of Chemical Engineering, Delft University of Technology, van der Maasweg 9, 2629, HZ, Delft, The Netherlands
| | - Krzysztof Galkowski
- Laboratoire National des Champs Magnetiques Intenses, CNRS-UJF-UPS-INSA, 143 avenue de Rangueil, 31400, Toulouse, France
- Faculty of Physics, Institute of Experimental Physics, University of Warsaw - Pasteura 5, 02-093, Warsaw, Poland
| | - Roberto Brenes
- Research Laboratory of Electronics, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA
| | - Duncan K Maude
- Laboratoire National des Champs Magnetiques Intenses, CNRS-UJF-UPS-INSA, 143 avenue de Rangueil, 31400, Toulouse, France
| | - Robin J Nicholas
- University of Oxford, Clarendon Laboratory, Parks Road, Oxford, OX1 3PU, UK
| | - Paulina Plochocka
- Laboratoire National des Champs Magnetiques Intenses, CNRS-UJF-UPS-INSA, 143 avenue de Rangueil, 31400, Toulouse, France
| | - Vladimir Bulović
- Research Laboratory of Electronics, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA
| | - Tom J Savenije
- Opto-electronic Materials Section, Department of Chemical Engineering, Delft University of Technology, van der Maasweg 9, 2629, HZ, Delft, The Netherlands
| | - Samuel D Stranks
- Research Laboratory of Electronics, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA
- Cavendish Laboratory, JJ Thomson Avenue, Cambridge, CB3 0HE, UK
| |
Collapse
|
21
|
Liu Q, Wang Y, Sui N, Wang Y, Chi X, Wang Q, Chen Y, Ji W, Zou L, Zhang H. Exciton Relaxation Dynamics in Photo-Excited CsPbI3 Perovskite Nanocrystals. Sci Rep 2016; 6:29442. [PMID: 27405786 PMCID: PMC4942613 DOI: 10.1038/srep29442] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Accepted: 06/20/2016] [Indexed: 12/20/2022] Open
Abstract
The exciton relaxation process of CsPbI3 perovskite nanocrystals (NCs) has been investigated by using transient absorption (TA) spectroscopy. The hot exciton relaxation process is confirmed to exist in the CsPbI3 NCs, through comparing the TA data of CsPbI3 NCs in low and high energy excitonic states. In addition, the Auger recombination and intrinsic decay paths also participate in the relaxation process of CsPbI3 NCs, even the number of exciton per NC is estimated to be less than 1. Excitation intensity-dependent TA data further confirms the existence of Auger recombination. Meanwhile, the spectral data also confirms that the weight of hot exciton also increase together with that of Auger recombination at high excitation intensity when CsPbI3 NCs in high energy excitonic states.
Collapse
Affiliation(s)
- Qinghui Liu
- Femtosecond Laser Laboratory, Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of Physics, Jilin University, Changchun 130012, P. R. China
| | - Yinghui Wang
- Femtosecond Laser Laboratory, Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of Physics, Jilin University, Changchun 130012, P. R. China
| | - Ning Sui
- Femtosecond Laser Laboratory, Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of Physics, Jilin University, Changchun 130012, P. R. China
| | - Yanting Wang
- Femtosecond Laser Laboratory, Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of Physics, Jilin University, Changchun 130012, P. R. China
| | - Xiaochun Chi
- Femtosecond Laser Laboratory, Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of Physics, Jilin University, Changchun 130012, P. R. China
| | - Qianqian Wang
- Femtosecond Laser Laboratory, Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of Physics, Jilin University, Changchun 130012, P. R. China
| | - Ying Chen
- Femtosecond Laser Laboratory, Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of Physics, Jilin University, Changchun 130012, P. R. China
| | - Wenyu Ji
- Femtosecond Laser Laboratory, Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of Physics, Jilin University, Changchun 130012, P. R. China
| | - Lu Zou
- Femtosecond Laser Laboratory, Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of Physics, Jilin University, Changchun 130012, P. R. China
| | - Hanzhuang Zhang
- Femtosecond Laser Laboratory, Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of Physics, Jilin University, Changchun 130012, P. R. China
| |
Collapse
|
22
|
Manser JS, Christians JA, Kamat PV. Intriguing Optoelectronic Properties of Metal Halide Perovskites. Chem Rev 2016; 116:12956-13008. [DOI: 10.1021/acs.chemrev.6b00136] [Citation(s) in RCA: 1067] [Impact Index Per Article: 133.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Joseph S. Manser
- Radiation
Laboratory, University of Notre Dame, Notre Dame, Indiana 46556, United States
- Department of Chemical & Biomolecular Engineering, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Jeffrey A. Christians
- Radiation
Laboratory, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Prashant V. Kamat
- Radiation
Laboratory, University of Notre Dame, Notre Dame, Indiana 46556, United States
- Department of Chemical & Biomolecular Engineering, University of Notre Dame, Notre Dame, Indiana 46556, United States
- Department of Chemistry & Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| |
Collapse
|
23
|
Affiliation(s)
- Joseph S. Manser
- Radiation
Laboratory, University of Notre Dame, Notre Dame, Indiana 46556, United States
- Department of Chemical & Biomolecular Engineering, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Jeffrey A. Christians
- Radiation
Laboratory, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Prashant V. Kamat
- Radiation
Laboratory, University of Notre Dame, Notre Dame, Indiana 46556, United States
- Department of Chemical & Biomolecular Engineering, University of Notre Dame, Notre Dame, Indiana 46556, United States
- Department of Chemistry & Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| |
Collapse
|
24
|
The Role of Trap-assisted Recombination in Luminescent Properties of Organometal Halide CH3NH3PbBr3 Perovskite Films and Quantum Dots. Sci Rep 2016; 6:27286. [PMID: 27249792 PMCID: PMC4888750 DOI: 10.1038/srep27286] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Accepted: 05/13/2016] [Indexed: 11/18/2022] Open
Abstract
Hybrid metal halide perovskites have been paid enormous attentions in photophysics research, whose excellent performances were attributed to their intriguing charge carriers proprieties. However, it still remains far from satisfaction in the comprehensive understanding of perovskite charge-transport properities, especially about trap-assisted recombination process. In this Letter, through time-resolved transient absorption (TA) and photoluminescence (PL) measurements, we provided a relative comprehensive investigation on the charge carriers recombination dynamics of CH3NH3PbBr3 (MAPbBr3) perovskite films and quantum dots (QDs), especially about trap-assisted recombination. It was found that the integral recombination mode of MAPbBr3 films was highly sensitive to the density distribution of generated charge carriers and trap states. Additional, Trap effects would be gradually weakened with elevated carrier densities. Furthermore, the trap-assisted recombination can be removed from MAPbBr3 QDs through its own surface passivation mechanism and this specialty may render the QDs as a new material in illuminating research. This work provides deeper physical insights into the dynamics processes of MAPbBr3 materials and paves a way toward more light-harvesting applications in future.
Collapse
|
25
|
Simpson MJ, Doughty B, Yang B, Xiao K, Ma YZ. Imaging Electronic Trap States in Perovskite Thin Films with Combined Fluorescence and Femtosecond Transient Absorption Microscopy. J Phys Chem Lett 2016; 7:1725-31. [PMID: 27103096 DOI: 10.1021/acs.jpclett.6b00715] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Charge carrier trapping degrades the performance of organometallic halide perovskite solar cells. To characterize the locations of electronic trap states in a heterogeneous photoactive layer, a spatially resolved approach is essential. Here, we report a comparative study on methylammonium lead tri-iodide perovskite thin films subject to different thermal annealing times using a combined photoluminescence (PL) and femtosecond transient absorption microscopy (TAM) approach to spatially map trap states. This approach coregisters the initially populated electronic excited states with the regions that recombine radiatively. Although the TAM images are relatively homogeneous for both samples, the corresponding PL images are highly structured. The remarkable variation in the PL intensities as compared to transient absorption signal amplitude suggests spatially dependent PL quantum efficiency, indicative of trapping events. Detailed analysis enables identification of two trapping regimes: a densely packed trapping region and a sparse trapping area that appear as unique spatial features in scaled PL maps.
Collapse
Affiliation(s)
- Mary Jane Simpson
- Chemical Sciences Division, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States
| | - Benjamin Doughty
- Chemical Sciences Division, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States
| | - Bin Yang
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States
| | - Kai Xiao
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States
| | - Ying-Zhong Ma
- Chemical Sciences Division, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States
| |
Collapse
|
26
|
Doughty B, Simpson MJ, Yang B, Xiao K, Ma YZ. Simplification of femtosecond transient absorption microscopy data from CH₃NH₃PbI₃ perovskite thin films into decay associated amplitude maps. NANOTECHNOLOGY 2016; 27:114002. [PMID: 27308671 DOI: 10.1088/0957-4484/27/11/114002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
This work aims to simplify multi-dimensional femtosecond transient absorption microscopy (TAM) data into decay associated amplitude maps (DAAMs) that describe the spatial distributions of dynamical processes occurring on various characteristic timescales. Application of this method to TAM data obtained from a model methyl-ammonium lead iodide (CH3NH3PbI3) perovskite thin film allows us to simplify the data set comprising 68 time-resolved images into four DAAMs. These maps offer a simple means to visualize the complex electronic excited-state dynamics in this system by separating distinct dynamical processes evolving on characteristic timescales into individual spatial images. This approach provides new insight into subtle aspects of ultrafast relaxation dynamics associated with excitons and charge carriers in the perovskite thin film, which have recently been found to coexist at spatially distinct locations.
Collapse
|
27
|
Fischer MC, Wilson JW, Robles FE, Warren WS. Invited Review Article: Pump-probe microscopy. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:031101. [PMID: 27036751 PMCID: PMC4798998 DOI: 10.1063/1.4943211] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 02/07/2016] [Indexed: 05/17/2023]
Abstract
Multiphoton microscopy has rapidly gained popularity in biomedical imaging and materials science because of its ability to provide three-dimensional images at high spatial and temporal resolution even in optically scattering environments. Currently the majority of commercial and home-built devices are based on two-photon fluorescence and harmonic generation contrast. These two contrast mechanisms are relatively easy to measure but can access only a limited range of endogenous targets. Recent developments in fast laser pulse generation, pulse shaping, and detection technology have made accessible a wide range of optical contrasts that utilize multiple pulses of different colors. Molecular excitation with multiple pulses offers a large number of adjustable parameters. For example, in two-pulse pump-probe microscopy, one can vary the wavelength of each excitation pulse, the detection wavelength, the timing between the excitation pulses, and the detection gating window after excitation. Such a large parameter space can provide much greater molecular specificity than existing single-color techniques and allow for structural and functional imaging without the need for exogenous dyes and labels, which might interfere with the system under study. In this review, we provide a tutorial overview, covering principles of pump-probe microscopy and experimental setup, challenges associated with signal detection and data processing, and an overview of applications.
Collapse
Affiliation(s)
- Martin C Fischer
- Department of Chemistry, Duke University, Durham, North Carolina 27708, USA
| | - Jesse W Wilson
- Department of Chemistry, Duke University, Durham, North Carolina 27708, USA
| | - Francisco E Robles
- Department of Chemistry, Duke University, Durham, North Carolina 27708, USA
| | - Warren S Warren
- Departments of Chemistry, Biomedical Engineering, Physics, and Radiology, Duke University, Durham, North Carolina 27708, USA
| |
Collapse
|
28
|
Draguta S, Thakur S, Morozov YV, Wang Y, Manser JS, Kamat PV, Kuno M. Spatially Non-uniform Trap State Densities in Solution-Processed Hybrid Perovskite Thin Films. J Phys Chem Lett 2016; 7:715-21. [PMID: 26840877 DOI: 10.1021/acs.jpclett.5b02888] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The facile solution-processability of methylammonium lead halide (CH3NH3PbI3) perovskites has catalyzed the development of inexpensive, hybrid perovskite-based optoelectronics. It is apparent, though, that solution-processed CH3NH3PbI3 films possess local emission heterogeneities, stemming from electronic disorder in the material. Herein we investigate the spatially resolved emission properties of CH3NH3PbI3 thin films through detailed emission intensity versus excitation intensity measurements. These studies enable us to establish the existence of nonuniform trap density variations wherein regions of CH3NH3PbI3 films exhibit effective free carrier recombination while others exhibit emission dynamics strongly influenced by the presence of trap states. Such trap density variations lead to spatially varying emission quantum yields and correspondingly impact the performance of both methylammonium lead halide perovskite solar cells and other hybrid perovskite-based devices. Of additional note is that the observed spatial extent of the optical disorder extends over length scales greater than that of underlying crystalline domains, suggesting the existence of other factors, beyond grain boundary-related nonradiative recombination channels, which lead to significant intrafilm optical heterogeneities.
Collapse
Affiliation(s)
- Sergiu Draguta
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Siddharatha Thakur
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
- Nanotechnology Engineering, University of Waterloo , Waterloo, Ontario N2L 3G1, Canada
| | - Yurii V Morozov
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Yuanxing Wang
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Joseph S Manser
- Department of Chemical and Biomolecular Engineering, University of Notre Dame , Notre Dame, Indiana 46556, United States
- Radiation Laboratory, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Prashant V Kamat
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
- Department of Chemical and Biomolecular Engineering, University of Notre Dame , Notre Dame, Indiana 46556, United States
- Radiation Laboratory, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Masaru Kuno
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| |
Collapse
|
29
|
Piatkowski P, Cohen B, Kazim S, Ahmad S, Douhal A. How photon pump fluence changes the charge carrier relaxation mechanism in an organic–inorganic hybrid lead triiodide perovskite. Phys Chem Chem Phys 2016; 18:27090-27101. [DOI: 10.1039/c6cp02682f] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The fluence dependent charge carrier relaxation dynamics in a FAPbI3 polycrystalline thin film were measured using femtosecond transient absorption and terahertz spectroscopies.
Collapse
Affiliation(s)
- Piotr Piatkowski
- Departamento de Química Física
- Facultad de Ciencias Ambientales y Bioquímica and INAMOL
- Universidad de Castilla-La Mancha
- 45071 Toledo
- Spain
| | - Boiko Cohen
- Departamento de Química Física
- Facultad de Ciencias Ambientales y Bioquímica and INAMOL
- Universidad de Castilla-La Mancha
- 45071 Toledo
- Spain
| | | | | | - Abderrazzak Douhal
- Departamento de Química Física
- Facultad de Ciencias Ambientales y Bioquímica and INAMOL
- Universidad de Castilla-La Mancha
- 45071 Toledo
- Spain
| |
Collapse
|
30
|
Yang B, Mahjouri-Samani M, Rouleau CM, Geohegan DB, Xiao K. Low temperature synthesis of hierarchical TiO2 nanostructures for high performance perovskite solar cells by pulsed laser deposition. Phys Chem Chem Phys 2016; 18:27067-27072. [DOI: 10.1039/c6cp02896a] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
High aspect-ratio TiO2 nanostructures directly assembled with pulsed laser deposition could improve interfacial contact for superior perovskite photovoltaic cells.
Collapse
Affiliation(s)
- Bin Yang
- Center for Nanophase Materials Sciences
- Oak Ridge National Laboratory
- Oak Ridge
- USA
| | | | | | - David B. Geohegan
- Center for Nanophase Materials Sciences
- Oak Ridge National Laboratory
- Oak Ridge
- USA
| | - Kai Xiao
- Center for Nanophase Materials Sciences
- Oak Ridge National Laboratory
- Oak Ridge
- USA
| |
Collapse
|