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Dembski S, Schwarz T, Oppmann M, Bandesha ST, Schmid J, Wenderoth S, Mandel K, Hansmann J. Establishing and testing a robot-based platform to enable the automated production of nanoparticles in a flexible and modular way. Sci Rep 2023; 13:11440. [PMID: 37454142 DOI: 10.1038/s41598-023-38535-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2023] [Accepted: 07/10/2023] [Indexed: 07/18/2023] Open
Abstract
Robotic systems facilitate relatively simple human-robot interaction for non-robot experts, providing the flexibility to implement different processes. In this context, shorter process times, as well as an increased product and process quality could be achieved. Robots short time-consuming processes, take over ergonomically unfavorable tasks and work efficiently all the time. In addition, flexible production is possible while maintaining or even increasing safety. This study describes the successful development of a dual-arm robot-based modular infrastructure and the establishment of an automated process for the reproducible production of nanoparticles. As proof of concept, a manual synthesis protocol for silica nanoparticle preparation with a diameter of about 200 nm as building blocks for photonic crystals was translated into a fully automated process. All devices and components of the automated system were optimized and adapted according to the synthesis requirements. To demonstrate the benefit of the automated nanoparticle production, manual (synthesis done by lab technicians) and automated syntheses were benchmarked. To this end, different processing parameters (time of synthesis procedure, accuracy of dosage etc.) and the properties of the produced nanoparticles were compared. We demonstrate that the use of the robot not only increased the synthesis accuracy and reproducibility but reduced the personnel time and costs up to 75%.
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Affiliation(s)
- Sofia Dembski
- Fraunhofer Institute for Silicate Research ISC, Neunerplatz 2, 97082, Würzburg, Germany.
- Department of Tissue Engineering and Regenerative Medicine TERM, University Hospital Würzburg, Röntgenring 11, 97070, Würzburg, Germany.
| | - Thomas Schwarz
- Fraunhofer Institute for Silicate Research ISC, Neunerplatz 2, 97082, Würzburg, Germany
| | - Maximilian Oppmann
- Fraunhofer Institute for Silicate Research ISC, Neunerplatz 2, 97082, Würzburg, Germany
| | | | - Jörn Schmid
- Goldfuß Engineering GmbH, Laboratory Automation, 72336, Balingen, Germany
| | - Sarah Wenderoth
- Fraunhofer Institute for Silicate Research ISC, Neunerplatz 2, 97082, Würzburg, Germany
| | - Karl Mandel
- Fraunhofer Institute for Silicate Research ISC, Neunerplatz 2, 97082, Würzburg, Germany
- Department of Chemistry and Pharmacy, Friedrich-Alexander University Erlangen-Nürnberg (FAU), 91058, Erlangen, Germany
| | - Jan Hansmann
- Fraunhofer Institute for Silicate Research ISC, Neunerplatz 2, 97082, Würzburg, Germany
- Faculty of Electrical Engineering, University of Applied Sciences Würzburg-Schweinfurt, 97421, Schweinfurt, Germany
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2
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Sebastian V. Toward continuous production of high-quality nanomaterials using microfluidics: nanoengineering the shape, structure and chemical composition. NANOSCALE 2022; 14:4411-4447. [PMID: 35274121 DOI: 10.1039/d1nr06342a] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Over the last decade, a multitude of synthesis strategies has been reported for the production of high-quality nanoparticles. Wet-chemical methods are generally the most efficient synthesis procedures since high control of crystallinity and physicochemical properties can be achieved. However, a number of challenges remain from inadequate reaction control during the nanocrystallization process; specifically variability, selectivity, scalability and safety. These shortcomings complicate the synthesis, make it difficult to obtain a uniform product with desired properties, and present serious limitations for scaling the production of colloidal nanocrystals from academic studies to industrial applications. Continuous flow reactors based on microfluidic principles offer potential solutions and advantages. The reproducibility of reaction conditions in microfluidics and therefore product quality have proved to exceed those obtained by batch processing. Considering that in nanoparticles' production not only is it crucial to control the particle size distribution, but also the shape and chemical composition, this review presents an overview of the current state-of-the-art in synthesis of anisotropic and faceted nanostructures by using microfluidics techniques. The review surveys the available tools that enable shape and chemical control, including secondary growth methods, active segmented flow, and photoinduced shape conversion. In addition, emphasis is placed on the available approaches developed to tune the structure and chemical composition of nanomaterials in order to produce complex heterostructures in a continuous and reproducible fashion.
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Affiliation(s)
- Victor Sebastian
- Instituto de Nanociencia y Materiales de Aragón (INMA), CSIC-Universidad de Zaragoza, Zaragoza 50009, Spain.
- Department of Chemical Engineering and Environmental Technologies, University de Zaragoza, 50018, Zaragoza, Spain
- Networking Research Centre of Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), C/Monforte de Lemos, 3-5 Pabellón 11, 28029 Madrid, Spain
- Laboratorio de Microscopías Avanzadas, Universidad de Zaragoza, 50018 Zaragoza, Spain
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3
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Illath K, Kar S, Gupta P, Shinde A, Wankhar S, Tseng FG, Lim KT, Nagai M, Santra TS. Microfluidic nanomaterials: From synthesis to biomedical applications. Biomaterials 2021; 280:121247. [PMID: 34801251 DOI: 10.1016/j.biomaterials.2021.121247] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Revised: 11/05/2021] [Accepted: 11/08/2021] [Indexed: 12/18/2022]
Abstract
Microfluidic platforms gain popularity in biomedical research due to their attractive inherent features, especially in nanomaterials synthesis. This review critically evaluates the current state of the controlled synthesis of nanomaterials using microfluidic devices. We describe nanomaterials' screening in microfluidics, which is very relevant for automating the synthesis process for biomedical applications. We discuss the latest microfluidics trends to achieve noble metal, silica, biopolymer, quantum dots, iron oxide, carbon-based, rare-earth-based, and other nanomaterials with a specific size, composition, surface modification, and morphology required for particular biomedical application. Screening nanomaterials has become an essential tool to synthesize desired nanomaterials using more automated processes with high speed and repeatability, which can't be neglected in today's microfluidic technology. Moreover, we emphasize biomedical applications of nanomaterials, including imaging, targeting, therapy, and sensing. Before clinical use, nanomaterials have to be evaluated under physiological conditions, which is possible in the microfluidic system as it stimulates chemical gradients, fluid flows, and the ability to control microenvironment and partitioning multi-organs. In this review, we emphasize the clinical evaluation of nanomaterials using microfluidics which was not covered by any other reviews. In the future, the growth of new materials or modification in existing materials using microfluidics platforms and applications in a diversity of biomedical fields by utilizing all the features of microfluidic technology is expected.
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Affiliation(s)
- Kavitha Illath
- Department of Engineering Design, Indian Institute of Technology Madras, India
| | - Srabani Kar
- Department of Electrical Engineering, University of Cambridge, UK
| | - Pallavi Gupta
- Department of Engineering Design, Indian Institute of Technology Madras, India
| | - Ashwini Shinde
- Department of Engineering Design, Indian Institute of Technology Madras, India
| | - Syrpailyne Wankhar
- Department of Bioengineering, Christian Medical College Vellore, Vellore, India
| | - Fan-Gang Tseng
- Department of Engineering and System Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Ki-Taek Lim
- Department of Biosystems Engineering, Kangwon National University, South Korea
| | - Moeto Nagai
- Department of Mechanical Engineering, Toyohashi University of Technology, Aichi, Japan
| | - Tuhin Subhra Santra
- Department of Engineering Design, Indian Institute of Technology Madras, India.
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4
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Lu JM, Wang HF, Pan JZ, Fang Q. Research Progress of Microfluidic Technique in Synthesis of Micro/Nano Materials. ACTA CHIMICA SINICA 2021. [DOI: 10.6023/a21030086] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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5
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Volk AA, Epps RW, Abolhasani M. Accelerated Development of Colloidal Nanomaterials Enabled by Modular Microfluidic Reactors: Toward Autonomous Robotic Experimentation. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2004495. [PMID: 33289177 DOI: 10.1002/adma.202004495] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 08/03/2020] [Indexed: 05/09/2023]
Abstract
In recent years, microfluidic technologies have emerged as a powerful approach for the advanced synthesis and rapid optimization of various solution-processed nanomaterials, including semiconductor quantum dots and nanoplatelets, and metal plasmonic and reticular framework nanoparticles. These fluidic systems offer access to previously unattainable measurements and synthesis conditions at unparalleled efficiencies and sampling rates. Despite these advantages, microfluidic systems have yet to be extensively adopted by the colloidal nanomaterial community. To help bridge the gap, this progress report details the basic principles of microfluidic reactor design and performance, as well as the current state of online diagnostics and autonomous robotic experimentation strategies, toward the size, shape, and composition-controlled synthesis of various colloidal nanomaterials. By discussing the application of fluidic platforms in recent high-priority colloidal nanomaterial studies and their potential for integration with rapidly emerging artificial intelligence-based decision-making strategies, this report seeks to encourage interdisciplinary collaborations between microfluidic reactor engineers and colloidal nanomaterial chemists. Full convergence of these two research efforts offers significantly expedited and enhanced nanomaterial discovery, optimization, and manufacturing.
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Affiliation(s)
- Amanda A Volk
- Department of Chemical and Biomolecular Engineering, North Carolina State University, 911 Partners Way, Raleigh, NC, 27695, USA
| | - Robert W Epps
- Department of Chemical and Biomolecular Engineering, North Carolina State University, 911 Partners Way, Raleigh, NC, 27695, USA
| | - Milad Abolhasani
- Department of Chemical and Biomolecular Engineering, North Carolina State University, 911 Partners Way, Raleigh, NC, 27695, USA
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6
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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.
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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
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7
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Affiliation(s)
- Yun Ding
- Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zurich, 8093 Zürich, Switzerland
| | - Philip D. Howes
- Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zurich, 8093 Zürich, Switzerland
| | - Andrew J. deMello
- Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zurich, 8093 Zürich, Switzerland
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8
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Zhang C, Luan W, Huang Y, Yang F. Growth of perovskite nanocrystals in poly-tetra fluoroethylene based microsystem: on-line and off-line measurements. NANOTECHNOLOGY 2019; 30:145602. [PMID: 30630155 DOI: 10.1088/1361-6528/aafd3b] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Cesium lead halide perovskite nanocrystals are photoelectric nanomaterials that have potential applications in a variety of areas due to their excellent photoelectric and tunable photo luminescent properties. In this work, we investigate the synergetic effects of reaction temperature, reaction-capillary length and flow rate on the growth kinetics of perovskite nanocrystals in a PTFE-based microsystem and the photoluminescence characteristics of the perovskite nanocrystals both on-line and off-line. The on-line measurement finds that increasing the reaction temperature leads to the increase of the wavelength of the PL emission peak of the synthesized nanocrystals and reduces the average size of the perovskite nanocrystals synthesized in long reaction-capillaries. The intensity of the PL emission peak of the nanocrystals synthesized at different reaction temperatures decreases with the increase of the flow rate. The off-line measurement reveals that increasing the flow rate generally leads to the blueshift of the PL emission peaks and the decrease of the average size of the perovskite nanocrystals synthesized at the reaction temperature of 160 °C in the capillary length of 60 cm. Increasing temperature leads to the increase of the emission wavelength of the perovskite nanocrystals from 560 to 608 nm. The temperature dependence of the average size of the synthesized nanocrystals with the same synthesis conditions at different temperatures can be described by the Arrhenius relationship with an activation energy of 8.54 kJ mol-1. Five different cross-sections of the synthesized perovskite nanocrystals are observed, including rhombus, hexagon, rectangle, square and quadrangle with three of them being observed for the first time.
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Affiliation(s)
- Chengxi Zhang
- Key Laboratory of Pressure Systems and Safety (MOE), School of Mechanical and Power Engineering, East China University of Science and Technology, Shanghai 200237, People's Republic of China
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9
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Bolze H, Erfle P, Riewe J, Bunjes H, Dietzel A, Burg TP. A Microfluidic Split-Flow Technology for Product Characterization in Continuous Low-Volume Nanoparticle Synthesis. MICROMACHINES 2019; 10:mi10030179. [PMID: 30857317 PMCID: PMC6470898 DOI: 10.3390/mi10030179] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 02/26/2019] [Accepted: 03/05/2019] [Indexed: 12/31/2022]
Abstract
A key aspect of microfluidic processes is their ability to perform chemical reactions in small volumes under continuous flow. However, a continuous process requires stable reagent flow over a prolonged period. This can be challenging in microfluidic systems, as bubbles or particles easily block or alter the flow. Online analysis of the product stream can alleviate this problem by providing a feedback signal. When this signal exceeds a pre-defined range, the process can be re-adjusted or interrupted to prevent contamination. Here we demonstrate the feasibility of this concept by implementing a microfluidic detector downstream of a segmented-flow system for the synthesis of lipid nanoparticles. To match the flow rate through the detector to the measurement bandwidth independent of the synthesis requirements, a small stream is sidelined from the original product stream and routed through a measuring channel with 2 × 2 µm cross-section. The small size of the measuring channel prevents the entry of air plugs, which are inherent to our segmented flow synthesis device. Nanoparticles passing through the small channel were detected and characterized by quantitative fluorescence measurements. With this setup, we were able to count single nanoparticles. This way, we were able to detect changes in the particle synthesis affecting the size, concentration, or velocity of the particles in suspension. We envision that the flow-splitting scheme demonstrated here can be transferred to detection methods other than fluorescence for continuous monitoring and feedback control of microfluidic nanoparticle synthesis.
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Affiliation(s)
- Holger Bolze
- Max Planck Institute for Biophysical Chemistry, Göttingen 37077, Germany.
- Center of Pharmaceutical Engineering, Technische Universität Braunschweig, Braunschweig 38106, Germany.
| | - Peer Erfle
- Center of Pharmaceutical Engineering, Technische Universität Braunschweig, Braunschweig 38106, Germany.
- Institute of Microtechnology, Technische Universität Braunschweig, Braunschweig 38124, Germany.
| | - Juliane Riewe
- Center of Pharmaceutical Engineering, Technische Universität Braunschweig, Braunschweig 38106, Germany.
- Institut für Pharmazeutische Technologie, Technische Universität Braunschweig, Braunschweig 38106, Germany.
| | - Heike Bunjes
- Center of Pharmaceutical Engineering, Technische Universität Braunschweig, Braunschweig 38106, Germany.
- Institut für Pharmazeutische Technologie, Technische Universität Braunschweig, Braunschweig 38106, Germany.
| | - Andreas Dietzel
- Center of Pharmaceutical Engineering, Technische Universität Braunschweig, Braunschweig 38106, Germany.
- Institute of Microtechnology, Technische Universität Braunschweig, Braunschweig 38124, Germany.
| | - Thomas P Burg
- Max Planck Institute for Biophysical Chemistry, Göttingen 37077, Germany.
- Department of Electrical Engineering and Information Technology, Technische Universität Darmstadt, 64283 Darmstadt, Germany.
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10
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Jose NA, Zeng HC, Lapkin AA. Hydrodynamic assembly of two-dimensional layered double hydroxide nanostructures. Nat Commun 2018; 9:4913. [PMID: 30464298 PMCID: PMC6249219 DOI: 10.1038/s41467-018-07395-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 10/30/2018] [Indexed: 12/12/2022] Open
Abstract
Formation mechanisms of two-dimensional nanostructures in wet syntheses are poorly understood. Even more enigmatic is the influence of hydrodynamic forces. Here we use liquid flow cell transmission electron microscopy to show that layered double hydroxide, as a model material, may form via the oriented attachment of hexagonal nanoparticles; under hydrodynamic shear, oriented attachment is accelerated. To hydrodynamically manipulate the kinetics of particle growth and oriented attachment, we develop a microreactor with high and tunable shear rates, enabling control over particle size, crystallinity and aspect ratio. This work offers new insights in the formation of two-dimensional materials, provides a scalable yet precise synthesis method, and proposes new avenues for the rational engineering and scalable production of highly anisotropic nanostructures. While liquid-phase synthesis of 2D materials presents opportunities for large-scale production, achieving precise control over product quality, size and morphology remains challenging. Here, the authors show that hydrodynamic manipulation of nanoparticle assembly enables control over crystallinity, size and aspect ratio.
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Affiliation(s)
- Nicholas A Jose
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, Philippa Fawcett Drive CB3 0AS, UK.,Cambridge Centre for Advanced Research and Education in Singapore Ltd., 1 Create Way, CREATE Tower #05-05, Singapore, 138602, Singapore
| | - Hua Chun Zeng
- Cambridge Centre for Advanced Research and Education in Singapore Ltd., 1 Create Way, CREATE Tower #05-05, Singapore, 138602, Singapore.,Department of Chemical and Biomolecular Engineering, Faculty of Engineering, National University of Singapore, 10 Kent Ridge Crescent, Singapore, 119260, Singapore
| | - Alexei A Lapkin
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, Philippa Fawcett Drive CB3 0AS, UK. .,Cambridge Centre for Advanced Research and Education in Singapore Ltd., 1 Create Way, CREATE Tower #05-05, Singapore, 138602, Singapore.
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11
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Dressler O, Howes PD, Choo J, deMello AJ. Reinforcement Learning for Dynamic Microfluidic Control. ACS OMEGA 2018; 3:10084-10091. [PMID: 31459137 PMCID: PMC6644574 DOI: 10.1021/acsomega.8b01485] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 08/07/2018] [Indexed: 05/16/2023]
Abstract
Recent years have witnessed an explosion in the application of microfluidic techniques to a wide variety of problems in the chemical and biological sciences. Despite the many considerable advantages that microfluidic systems bring to experimental science, microfluidic platforms often exhibit inconsistent system performance when operated over extended timescales. Such variations in performance are because of a multiplicity of factors, including microchannel fouling, substrate deformation, temperature and pressure fluctuations, and inherent manufacturing irregularities. The introduction and integration of advanced control algorithms in microfluidic platforms can help mitigate such inconsistencies, paving the way for robust and repeatable long-term experiments. Herein, two state-of-the-art reinforcement learning algorithms, based on Deep Q-Networks and model-free episodic controllers, are applied to two experimental "challenges," involving both continuous-flow and segmented-flow microfluidic systems. The algorithms are able to attain superhuman performance in controlling and processing each experiment, highlighting the utility of novel control algorithms for automated high-throughput microfluidic experimentation.
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Affiliation(s)
- Oliver
J. Dressler
- Institute
for Chemical and Bioengineering, Department of Chemistry and Applied
Biosciences, ETH Zürich, Vladimir Prelog Weg 1, 8093 Zürich, Switzerland
| | - Philip D. Howes
- Institute
for Chemical and Bioengineering, Department of Chemistry and Applied
Biosciences, ETH Zürich, Vladimir Prelog Weg 1, 8093 Zürich, Switzerland
| | - Jaebum Choo
- Department
of Bionano Technology, Hanyang University, Ansan 426-791, South Korea
| | - Andrew J. deMello
- Institute
for Chemical and Bioengineering, Department of Chemistry and Applied
Biosciences, ETH Zürich, Vladimir Prelog Weg 1, 8093 Zürich, Switzerland
- E-mail: (A J.d.)
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12
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Huang H, du Toit H, Panariello L, Mazzei L, Gavriilidis A. Continuous synthesis of gold nanoparticles in micro- and millifluidic systems. PHYSICAL SCIENCES REVIEWS 2018. [DOI: 10.1515/psr-2017-0119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Gold nanomaterials have diverse applications ranging from healthcare and nanomedicine to analytical sciences and catalysis. Microfluidic and millifluidic reactors offer multiple advantages for their synthesis and manufacturing, including controlled or fast mixing, accurate reaction time control and excellent heat transfer. These advantages are demonstrated by reviewing gold nanoparticle synthesis strategies in flow devices. However, there are still challenges to be resolved, such as reactor fouling, particularly if robust manufacturing processes are to be developed to achieve the desired targets in terms of nanoparticle size, size distribution, surface properties, process throughput and robustness. Solutions to these challenges are more effective through a coordinated approach from chemists, engineers and physicists, which has at its core a qualitative and quantitative understanding of the synthesis processes and reactor operation. This is important as nanoparticle synthesis is complex, encompassing multiple phenomena interacting with each other, often taking place at short timescales. The proposed methodology for the development of reactors and processes is generic and contains various interconnected considerations. It aims to be a starting point towards rigorous design procedures for the robust and reproducible continuous flow synthesis of gold nanoparticles.
Graphical Abstract:
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Affiliation(s)
- He Huang
- Department of Chemical Engineering , University College London , Torrington Place , London WC1E 7JE , UK
| | - Hendrik du Toit
- Department of Chemical Engineering , University College London , Torrington Place , London WC1E 7JE , UK
| | - Luca Panariello
- Department of Chemical Engineering , University College London , Torrington Place , London WC1E 7JE , UK
| | - Luca Mazzei
- Department of Chemical Engineering , University College London , Torrington Place , London WC1E 7JE , UK
| | - Asterios Gavriilidis
- Department of Chemical Engineering , University College London , Torrington Place , London WC1E 7JE , UK
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13
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Bezinge L, Maceiczyk RM, Lignos I, Kovalenko MV, deMello AJ. Pick a Color MARIA: Adaptive Sampling Enables the Rapid Identification of Complex Perovskite Nanocrystal Compositions with Defined Emission Characteristics. ACS APPLIED MATERIALS & INTERFACES 2018; 10:18869-18878. [PMID: 29766716 DOI: 10.1021/acsami.8b03381] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Recent advances in the development of hybrid organic-inorganic lead halide perovskite (LHP) nanocrystals (NCs) have demonstrated their versatility and potential application in photovoltaics and as light sources through compositional tuning of optical properties. That said, due to their compositional complexity, the targeted synthesis of mixed-cation and/or mixed-halide LHP NCs still represents an immense challenge for traditional batch-scale chemistry. To address this limitation, we herein report the integration of a high-throughput segmented-flow microfluidic reactor and a self-optimizing algorithm for the synthesis of NCs with defined emission properties. The algorithm, named Multiparametric Automated Regression Kriging Interpolation and Adaptive Sampling (MARIA), iteratively computes optimal sampling points at each stage of an experimental sequence to reach a target emission peak wavelength based on spectroscopic measurements. We demonstrate the efficacy of the method through the synthesis of multinary LHP NCs, (Cs/FA)Pb(I/Br)3 (FA = formamidinium) and (Rb/Cs/FA)Pb(I/Br)3 NCs, using MARIA to rapidly identify reagent concentrations that yield user-defined photoluminescence peak wavelengths in the green-red spectral region. The procedure returns a robust model around a target output in far fewer measurements than systematic screening of parametric space and additionally enables the prediction of other spectral properties, such as, full-width at half-maximum and intensity, for conditions yielding NCs with similar emission peak wavelength.
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Affiliation(s)
| | | | | | - Maksym V Kovalenko
- Laboratory for Thin Films and Photovoltaics , Empa-Swiss Federal Laboratories for Materials Science and Technology , Überlandstrasse 129 , 8600 Dübendorf , Switzerland
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14
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Lignos I, Protesescu L, Emiroglu DB, Maceiczyk R, Schneider S, Kovalenko MV, deMello AJ. Unveiling the Shape Evolution and Halide-Ion-Segregation in Blue-Emitting Formamidinium Lead Halide Perovskite Nanocrystals Using an Automated Microfluidic Platform. NANO LETTERS 2018; 18:1246-1252. [PMID: 29337579 DOI: 10.1021/acs.nanolett.7b04838] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Hybrid organic-inorganic perovskites and in particular formamidinium lead halide (FAPbX3, X = Cl, Br, I) perovskite nanocrystals (NCs) have shown great promise for their implementation in optoelectronic devices. Specifically, the Br and I counterparts have shown unprecedented photoluminescence properties, including precise wavelength tuning (530-790 nm), narrow emission linewidths (<100 meV) and high photoluminescence quantum yields (70-90%). However, the controlled formation of blue emitting FAPb(Cl1-xBrx)3 NCs lags behind their green and red counterparts and the mechanism of their formation remains unclear. Herein, we report the formation of FAPb(Cl1-xBrx)3 NCs with stable emission between 440 and 520 nm in a fully automated droplet-based microfluidic reactor and subsequent reaction upscaling in conventional laboratory glassware. The thorough parametric screening allows for the elucidation of parametric zones (FA-to-Pb and Br-to-Cl molar ratios, temperature, and excess oleic acid) for the formation of nanoplatelets and/or NCs. In contrast to CsPb(Cl1-xBrx)3 NCs, based on online parametric screening and offline structural characterization, we demonstrate that the controlled synthesis of Cl-rich perovskites (above 60 at% Cl) with stable emission remains a challenge due to fast segregation of halide ions.
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Affiliation(s)
- Ioannis Lignos
- Department of Chemistry and Applied Biosciences, Institute for Chemical and Bioengineering, ETH Zürich , Vladimir-Prelog-Weg 1, Zurich 8093, Switzerland
| | - Loredana Protesescu
- Department of Chemistry and Applied Biosciences, Institute of Inorganic Chemistry, ETH Zürich , Vladimir-Prelog-Weg 1, Zurich 8093, Switzerland
- Empa-Swiss Federal Laboratories for Materials Science and Technology , Überlandstrasse 129, Zurich 8600, Switzerland
| | - Dilara Börte Emiroglu
- Department of Chemistry and Applied Biosciences, Institute for Chemical and Bioengineering, ETH Zürich , Vladimir-Prelog-Weg 1, Zurich 8093, Switzerland
| | - Richard Maceiczyk
- Department of Chemistry and Applied Biosciences, Institute for Chemical and Bioengineering, ETH Zürich , Vladimir-Prelog-Weg 1, Zurich 8093, Switzerland
| | - Simon Schneider
- Department of Chemistry and Applied Biosciences, Institute of Inorganic Chemistry, ETH Zürich , Vladimir-Prelog-Weg 1, Zurich 8093, Switzerland
- Empa-Swiss Federal Laboratories for Materials Science and Technology , Überlandstrasse 129, Zurich 8600, Switzerland
| | - Maksym V Kovalenko
- Department of Chemistry and Applied Biosciences, Institute of Inorganic Chemistry, ETH Zürich , Vladimir-Prelog-Weg 1, Zurich 8093, Switzerland
- Empa-Swiss Federal Laboratories for Materials Science and Technology , Überlandstrasse 129, Zurich 8600, Switzerland
| | - Andrew J deMello
- Department of Chemistry and Applied Biosciences, Institute for Chemical and Bioengineering, ETH Zürich , Vladimir-Prelog-Weg 1, Zurich 8093, Switzerland
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15
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Pan LJ, Tu JW, Ma HT, Yang YJ, Tian ZQ, Pang DW, Zhang ZL. Controllable synthesis of nanocrystals in droplet reactors. LAB ON A CHIP 2017; 18:41-56. [PMID: 29098217 DOI: 10.1039/c7lc00800g] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
In recent years, a broad range of nanocrystals have been synthesized in droplet-based microfluidic reactors which provide obvious advantages, such as accurate manipulation, better reproducibility and reliable automation. In this review, we initially introduce general concepts of droplet reactors followed by discussions of their main functional regions including droplet generation, mixing of reactants, reaction controlling, in situ monitoring, and reaction quenching. Subsequently, the enhanced mass and heat transport properties are discussed. Next, we focus on research frontiers including sequential multistep synthesis, intelligent synthesis, reliable scale-up synthesis, and interfacial synthesis. Finally, we end with an outlook on droplet reactors, especially highlighting some aspects such as large-scale production, the integrated process of synthesis and post-synthetic treatments, automated droplet reactors with in situ monitoring and optimizing algorithms, and rapidly developing strategies for interfacial synthesis.
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Affiliation(s)
- Liang-Jun Pan
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Science, Wuhan University, Wuhan 430072, People's Republic of China.
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16
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Liu Y, Jiang X. Why microfluidics? Merits and trends in chemical synthesis. LAB ON A CHIP 2017; 17:3960-3978. [PMID: 28913530 DOI: 10.1039/c7lc00627f] [Citation(s) in RCA: 126] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The intrinsic limitations of conventional batch synthesis have hindered its applications in both solving classical problems and exploiting new frontiers. Microfluidic technology offers a new platform for chemical synthesis toward either molecules or materials, which has promoted the progress of diverse fields such as organic chemistry, materials science, and biomedicine. In this review, we focus on the improved performance of microreactors in handling various situations, and outline the trend of microfluidic synthesis (microsynthesis, μSyn) from simple microreactors to integrated microsystems. Examples of synthesizing both chemical compounds and micro/nanomaterials show the flexible applications of this approach. We aim to provide strategic guidance for the rational design, fabrication, and integration of microdevices for synthetic use. We critically evaluate the existing challenges and future opportunities associated with this burgeoning field.
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Affiliation(s)
- Yong Liu
- Beijing Engineering Research Center for BioNanotechnology & CAS Key Laboratory for Biological Effects of Nanomaterials and Nanosafety, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, P. R. China.
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17
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Maceiczyk RM, Hess D, Chiu FWY, Stavrakis S, deMello AJ. Differential detection photothermal spectroscopy: towards ultra-fast and sensitive label-free detection in picoliter & femtoliter droplets. LAB ON A CHIP 2017; 17:3654-3663. [PMID: 28967022 DOI: 10.1039/c7lc00946a] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Despite the growing importance of droplet-based microfluidics in high-throughput experimentation, few current methods allow the sensitive measurement of absorbance within rapidly moving droplets. To address this significant limitation, we herein present the application of differential detection photothermal interferometry (DDPI) for single-point absorbance quantification in pL- and fL-volume droplets. To assess the efficacy of our approach, we initially measure absorbance in 100 pL droplets at frequencies in excess of 1 kHz and determine a detection limit of 1.4 μmol L-1 for Erythrosin B (A = 3.8 × 10-4). Subsequently, we apply the method to the analysis of fL-volume droplets and droplets generated at frequencies in excess of 10 kHz. Finally, we demonstrate the utility of DDPI as a detection scheme for colorimetric assays. Specifically, we extract the Michaelis-Menten constant for the reaction of β-galactosidase and chlorophenol-red-β-d-galactopyranoside and monitor the metabolomic activity of a population of HL-60 cells at the single cell level. Results establish single-point absorbance detection as a powerful, sensitive and rapid alternative to fluorescence for a wide range of assays within segmented flows.
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Affiliation(s)
- Richard M Maceiczyk
- Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 1, 8093 Zürich, Switzerland.
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18
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Santana JS, Koczkur KM, Skrabalak SE. Synthesis of Core@Shell Nanostructures in a Continuous Flow Droplet Reactor: Controlling Structure through Relative Flow Rates. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:6054-6061. [PMID: 28586227 DOI: 10.1021/acs.langmuir.7b00680] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Bimetallic nanostructures are primarily synthesized in small volume batches. However, droplet-based reactors are receiving attention due to their ability to maintain thermal and compositional equilibrium within and between droplets, enabling flow operations for inline analyses and the scale-up of nanomaterial syntheses. Here, the syntheses of shape-controlled core@shell Au@Pd nanostructures with variable shell thicknesses are reported through control of the relative flow rates of reagents within the microreactor. Specifically, Pd shells were grown on cubic or octahedral Au seeds, selected as a model system. In batch reactions, shell thickness is determined by precursor concentration; however, as shown here, precursor feedstock concentration can be held constant, with the precursor concentration within the droplets being controlled through relative flow rates. This approach allows process conditions to be modified inline rather than from batch to batch to achieve particles with different shell thicknesses, and this procedure should be applicable to other multicomponent systems.
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Affiliation(s)
- Joshua S Santana
- Department of Chemistry, Indiana University , 800 E. Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Kallum M Koczkur
- Department of Chemistry, Indiana University , 800 E. Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Sara E Skrabalak
- Department of Chemistry, Indiana University , 800 E. Kirkwood Avenue, Bloomington, Indiana 47405, United States
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19
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Dressler OJ, Casadevall I Solvas X, deMello AJ. Chemical and Biological Dynamics Using Droplet-Based Microfluidics. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2017; 10:1-24. [PMID: 28375703 DOI: 10.1146/annurev-anchem-061516-045219] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Recent years have witnessed an increased use of droplet-based microfluidic techniques in a wide variety of chemical and biological assays. Nevertheless, obtaining dynamic data from these platforms has remained challenging, as this often requires reading the same droplets (possibly thousands of them) multiple times over a wide range of intervals (from milliseconds to hours). In this review, we introduce the elemental techniques for the formation and manipulation of microfluidic droplets, together with the most recent developments in these areas. We then discuss a wide range of analytical methods that have been successfully adapted for analyte detection in droplets. Finally, we highlight a diversity of studies where droplet-based microfluidic strategies have enabled the characterization of dynamic systems that would otherwise have remained unexplorable.
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Affiliation(s)
- Oliver J Dressler
- Department of Chemistry and Applied Biosciences, ETH Zürich, CH-8093 Zürich, Switzerland;
| | | | - Andrew J deMello
- Department of Chemistry and Applied Biosciences, ETH Zürich, CH-8093 Zürich, Switzerland;
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20
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Lignos I, Maceiczyk R, deMello AJ. Microfluidic Technology: Uncovering the Mechanisms of Nanocrystal Nucleation and Growth. Acc Chem Res 2017; 50:1248-1257. [PMID: 28467055 DOI: 10.1021/acs.accounts.7b00088] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The controlled and reproducible formation of colloidal semiconductor nanocrystals (or quantum dots) is of central importance in nanoscale science and technology. The tunable size- and shape-dependent properties of such materials make them ideal candidates for the development of efficient and low-cost displays, solar cells, light-emitting devices, and catalysts. The formidable difficulties associated with the macroscale preparation of semiconductor nanocrystals (possessing bespoke optical and chemical properties) result from the fact that underlying reaction mechanisms are complex and that the reactive environment is difficult to control. Automated microfluidic reactors coupled with monitoring systems and optimization algorithms aim to elucidate complex reaction mechanisms that govern both nucleation and growth of nanocrystals. Such platforms are ideally suited for the efficient optimization of reaction parameters, assuring the reproducible synthesis of nanocrystals with user-defined properties. This Account aims to inform the nanomaterials community about how microfluidic technologies can supplement flask experimentation for the ensemble investigation of formation mechanisms and design of semiconductor nanocrystals. We present selected studies outlining the preparation of quantum dots using microfluidic systems with integrated analytics. Such microfluidic reaction systems leverage the ability to extract real-time information regarding optical, structural, and compositional characteristics of quantum dots during nucleation and growth stages. The Account further highlights our recent research activities focused on the development and application of droplet-based microfluidics with integrated optical detection systems for the efficient and rapid screening of reaction conditions and a better understanding of the mechanisms of quantum dot synthesis. We describe the features and operation of fully automated microfluidic reactors and their subsequent application to high-throughput parametric screening of metal chalcogenides (CdSe, PbS, PbSe, CdSeTe), ternary and core/shell heavy metal-free quantum dots (CuInS2, CuInS2/ZnS), and all-inorganic perovskite nanocrystals (CsPbX3, X = Cl, Br, I) syntheses. Critically, concurrent absorption and photoluminescence measurements on millisecond to second time scales allow the extraction of basic parameters governing nanocrystal formation. Moreover, experimental data obtained from such microfluidic platforms can be directly supported by theoretical models of nucleation and growth. To this end, we also describe the use of metamodeling algorithms able to accurately predict optimized conditions of CdSe synthesis using a minimal number of sample parameters. Importantly, we discuss future challenges that must be addressed before microfluidic technologies are in a position to be widely adopted for the on-demand formation of nanocrystals. From a technology perspective, these challenges include the development of novel engineering platforms for the formation of complex architectures, the integration of monitoring systems able to harvest photophysical and structural information, the incorporation of continuous purification systems, and the application of optimization algorithms to multicomponent quantum dot systems.
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Affiliation(s)
- Ioannis Lignos
- Institute for Chemical
and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 1, Zurich 8093, Switzerland
| | - Richard Maceiczyk
- Institute for Chemical
and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 1, Zurich 8093, Switzerland
| | - Andrew J. deMello
- Institute for Chemical
and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 1, Zurich 8093, Switzerland
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21
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Chiu DT, deMello AJ, Di Carlo D, Doyle PS, Hansen C, Maceiczyk RM, Wootton RC. Small but Perfectly Formed? Successes, Challenges, and Opportunities for Microfluidics in the Chemical and Biological Sciences. Chem 2017. [DOI: 10.1016/j.chempr.2017.01.009] [Citation(s) in RCA: 212] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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22
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Maceiczyk R, Shimizu H, Müller D, Kitamori T, deMello A. A Photothermal Spectrometer for Fast and Background-Free Detection of Individual Nanoparticles in Flow. Anal Chem 2017; 89:1994-1999. [DOI: 10.1021/acs.analchem.6b04540] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Richard Maceiczyk
- Institute
for Chemical and Bioengineering, Department of Chemistry and Applied
Biosciences, ETH Zürich, Vladimir-Prelog-Weg 1, 8093 Zürich, Switzerland
| | - Hisashi Shimizu
- Department
of Applied Chemistry, School of Engineering, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - David Müller
- Institute
for Chemical and Bioengineering, Department of Chemistry and Applied
Biosciences, ETH Zürich, Vladimir-Prelog-Weg 1, 8093 Zürich, Switzerland
- Centre Suisse d’Electronique et de Microtechnique (CSEM), Bahnhofstrasse 1, 7302 Landquart, Switzerland
| | - Takehiko Kitamori
- Department
of Applied Chemistry, School of Engineering, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Andrew deMello
- Institute
for Chemical and Bioengineering, Department of Chemistry and Applied
Biosciences, ETH Zürich, Vladimir-Prelog-Weg 1, 8093 Zürich, Switzerland
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23
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Lignos I, Stavrakis S, Nedelcu G, Protesescu L, deMello AJ, Kovalenko MV. Synthesis of Cesium Lead Halide Perovskite Nanocrystals in a Droplet-Based Microfluidic Platform: Fast Parametric Space Mapping. NANO LETTERS 2016; 16:1869-77. [PMID: 26836149 DOI: 10.1021/acs.nanolett.5b04981] [Citation(s) in RCA: 218] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Prior to this work, fully inorganic nanocrystals of cesium lead halide perovskite (CsPbX3, X = Br, I, Cl and Cl/Br and Br/I mixed halide systems), exhibiting bright and tunable photoluminescence, have been synthesized using conventional batch (flask-based) reactions. Unfortunately, our understanding of the parameters governing the formation of these nanocrystals is still very limited due to extremely fast reaction kinetics and multiple variables involved in ion-metathesis-based synthesis of such multinary halide systems. Herein, we report the use of a droplet-based microfluidic platform for the synthesis of CsPbX3 nanocrystals. The combination of online photoluminescence and absorption measurements and the fast mixing of reagents within such a platform allows the rigorous and rapid mapping of the reaction parameters, including molar ratios of Cs, Pb, and halide precursors, reaction temperatures, and reaction times. This translates into enormous savings in reagent usage and screening times when compared to analogous batch synthetic approaches. The early-stage insight into the mechanism of nucleation of metal halide nanocrystals suggests similarities with multinary metal chalcogenide systems, albeit with much faster reaction kinetics in the case of halides. Furthermore, we show that microfluidics-optimized synthesis parameters are also directly transferrable to the conventional flask-based reaction.
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Affiliation(s)
| | | | - Georgian Nedelcu
- Empa-Swiss Federal Laboratories for Materials Science and Technology , Überlandstrasse 129, 8600, Dübendorf, Switzerland
| | - Loredana Protesescu
- Empa-Swiss Federal Laboratories for Materials Science and Technology , Überlandstrasse 129, 8600, Dübendorf, Switzerland
| | | | - Maksym V Kovalenko
- Empa-Swiss Federal Laboratories for Materials Science and Technology , Überlandstrasse 129, 8600, Dübendorf, Switzerland
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24
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Maceiczyk RM, Bezinge L, deMello AJ. Kinetics of nanocrystal synthesis in a microfluidic reactor: theory and experiment. REACT CHEM ENG 2016. [DOI: 10.1039/c6re00073h] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
A two-stage microreactor enables the quantitative evaluation of a kinetic model of nanocrystal nucleation and growth.
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Affiliation(s)
- Richard M. Maceiczyk
- Department of Chemistry and Applied Biosciences
- Institute of Chemical and Bioengineering
- ETH Zürich
- 8093 Zürich
- Switzerland
| | - Leonard Bezinge
- Department of Chemistry and Applied Biosciences
- Institute of Chemical and Bioengineering
- ETH Zürich
- 8093 Zürich
- Switzerland
| | - Andrew J. deMello
- Department of Chemistry and Applied Biosciences
- Institute of Chemical and Bioengineering
- ETH Zürich
- 8093 Zürich
- Switzerland
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