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Lee Y, Buchheim J, Hellenkamp B, Lynall D, Yang K, Young EF, Penkov B, Sia S, Stojanovic MN, Shepard KL. Carbon-nanotube field-effect transistors for resolving single-molecule aptamer-ligand binding kinetics. Nat Nanotechnol 2024:10.1038/s41565-023-01591-0. [PMID: 38233588 DOI: 10.1038/s41565-023-01591-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 12/11/2023] [Indexed: 01/19/2024]
Abstract
Small molecules such as neurotransmitters are critical for biochemical functions in living systems. While conventional ultraviolet-visible spectroscopy and mass spectrometry lack portability and are unsuitable for time-resolved measurements in situ, techniques such as amperometry and traditional field-effect detection require a large ensemble of molecules to reach detectable signal levels. Here we demonstrate the potential of carbon-nanotube-based single-molecule field-effect transistors (smFETs), which can detect the charge on a single molecule, as a new platform for recognizing and assaying small molecules. smFETs are formed by the covalent attachment of a probe molecule, in our case a DNA aptamer, to a carbon nanotube. Conformation changes on binding are manifest as discrete changes in the nanotube electrical conductance. By monitoring the kinetics of conformational changes in a binding aptamer, we show that smFETs can detect and quantify serotonin at the single-molecule level, providing unique insights into the dynamics of the aptamer-ligand system. In particular, we show the involvement of G-quadruplex formation and the disruption of the native hairpin structure in the conformational changes of the serotonin-aptamer complex. The smFET is a label-free approach to analysing molecular interactions at the single-molecule level with high temporal resolution, providing additional insights into complex biological processes.
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Affiliation(s)
- Yoonhee Lee
- Department of Electrical Engineering, Columbia University, New York, NY, USA
- Division of Electronics & Information System, ICT Research Institute, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, Republic of Korea
| | - Jakob Buchheim
- Department of Electrical Engineering, Columbia University, New York, NY, USA
- Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR), Institute of Quantum Technologies, Ulm, Germany
| | - Björn Hellenkamp
- Department of Electrical Engineering, Columbia University, New York, NY, USA
| | - David Lynall
- Department of Electrical Engineering, Columbia University, New York, NY, USA
| | - Kyungae Yang
- Department of Medicine, Columbia University, New York, NY, USA
| | - Erik F Young
- Quicksilver Biosciences, Inc., New York, NY, USA
| | - Boyan Penkov
- Department of Electrical Engineering, Columbia University, New York, NY, USA
| | - Samuel Sia
- Department of Biomedical Engineering, Columbia University, New York, NY, USA
| | | | - Kenneth L Shepard
- Department of Electrical Engineering, Columbia University, New York, NY, USA.
- Department of Biomedical Engineering, Columbia University, New York, NY, USA.
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Siewert F, Buchheim J, Gwalt G, Bean R, Mancuso AP. On the characterization of a 1 m long, ultra-precise KB-focusing mirror pair for European XFEL by means of slope measuring deflectometry. Rev Sci Instrum 2019; 90:021713. [PMID: 30831716 DOI: 10.1063/1.5065473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Accepted: 12/01/2018] [Indexed: 06/09/2023]
Abstract
Recently, the European X-Ray Free Electron Laser (XFEL) has successfully produced its first X-ray photon pulse trains. This unique photon source will provide up to 27 000 photon pulses per second for experiments in different fields of science. In order to accomplish this, ultra-precise mirrors of dedicated shape are used to guide and focus these photons along beamlines of up to 930 m in length from the source in the undulator section to the desired focal point at an experimental station. We will report on a Kirkpatrick-Baez-mirror pair designed to focus hard-X-rays in the energy range from 3 to 16 keV to a 100 nm scale at the SPB/SFX instrument of the European XFEL. Both mirrors are elliptical cylinder-like shaped. The figure error of these 1 m long mirrors was specified to be better than 2 nm pv in terms of the height domain; this corresponds to a slope error of about 50 nrad rms (at least a best effort finishing is requested). This is essential to provide optimal experimental conditions including preservation of brilliance and wavefront. Such large and precise optics represents a challenge for the required deterministic surface polishing technology, elastic emission machining in this case, as well as for the metrology mandatory to enable a precise characterization of the topography on the mirror aperture. Besides the slope errors, the ellipse parameters are also of particular interest. The mirrors were under inspection by means of slope measuring deflectometry at the BESSY-NOM slope measuring profiler at the Helmholtz Zentrum Berlin. The NOM measurements have shown a slope error of 100 nrad rms on a aperture length of 950 mm corresponding to a residual figure deviation ≤20 nm pv for both mirrors. Additionally we found a strong impact of the mirror support conditions on the mirror shape finally measured. We will report on the measurement concept to characterize such mirrors as well as to discuss the achieved results.
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Affiliation(s)
- F Siewert
- Helmholtz Zentrum Berlin für Materialien und Energie, Department Optics and Beamlines, Albert-Einstein-Str. 15, 12489 Berlin, Germany
| | - J Buchheim
- Helmholtz Zentrum Berlin für Materialien und Energie, Department Optics and Beamlines, Albert-Einstein-Str. 15, 12489 Berlin, Germany
| | - G Gwalt
- Helmholtz Zentrum Berlin für Materialien und Energie, Department Optics and Beamlines, Albert-Einstein-Str. 15, 12489 Berlin, Germany
| | - R Bean
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | - A P Mancuso
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
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Abstract
Driven by the need of maximizing performance, membrane nanofabrication strives for ever thinner materials aiming to increase permeation while evoking inherent challenges stemming from mechanical stability and defects. We investigate this thickness rationale by studying viscous transport mechanisms across nanopores when transitioning the membrane thickness from infinitely thin to finite values. We synthesize double-layer graphene membranes containing pores with diameters from ∼6 to 1000 nm to investigate liquid permeation over a wide range of viscosities and pressures. Nanoporous membranes with thicknesses up to 90 nm realized by atomic layer deposition demonstrate dominance of the entrance resistance for aspect ratios up to one. Liquid permeation across these atomically thin pores is limited by viscous dissipation at the pore entrance. Independent of thickness and universal for porous materials, this entrance resistance sets an upper bound to the viscous transport. Our results imply that membranes with near-ultimate permeation should feature rationally selected thicknesses based on the target solute size for applications ranging from osmosis to microfiltration and introduce a proper perspective to the pursuit of ever thinner membranes.
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Affiliation(s)
- Jakob Buchheim
- Nanoscience for Energy Technology and Sustainability, Department of Mechanical and Process Engineering , Eidgenössische Technische Hochschule (ETH) Zürich , Tannenstrasse 3 , Zürich CH-8092 , Switzerland
| | - Karl-Philipp Schlichting
- Laboratory of Thermodynamics in Emerging Technologies Department of Mechanical and Process Engineering , Eidgenössische Technische Hochschule (ETH) Zürich , Tannenstrasse 3 , Zürich CH-8092 , Switzerland
| | - Roman M Wyss
- Institute of Soft Materials Department of Material Sciences , Eidgenössische Technische Hochschule (ETH) Zürich , Vladimir-Prelog-Weg 1-5 , Zürich CH-8093 , Switzerland
| | - Hyung Gyu Park
- Nanoscience for Energy Technology and Sustainability, Department of Mechanical and Process Engineering , Eidgenössische Technische Hochschule (ETH) Zürich , Tannenstrasse 3 , Zürich CH-8092 , Switzerland
- Mechanical Engineering Pohang University of Science and Technology (POSTECH) , 77 Cheongam-ro , Nam-gu, Pohang , Gyeongbuk 37673 , Republic of Korea
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Siewert F, Löchel B, Buchheim J, Eggenstein F, Firsov A, Gwalt G, Kutz O, Lemke S, Nelles B, Rudolph I, Schäfers F, Seliger T, Senf F, Sokolov A, Waberski C, Wolf J, Zeschke T, Zizak I, Follath R, Arnold T, Frost F, Pietag F, Erko A. Gratings for synchrotron and FEL beamlines: a project for the manufacture of ultra-precise gratings at Helmholtz Zentrum Berlin. J Synchrotron Radiat 2018; 25:91-99. [PMID: 29271757 PMCID: PMC5741124 DOI: 10.1107/s1600577517015600] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Accepted: 10/26/2017] [Indexed: 05/27/2023]
Abstract
Blazed gratings are of dedicated interest for the monochromatization of synchrotron radiation when a high photon flux is required, such as, for example, in resonant inelastic X-ray scattering experiments or when the use of laminar gratings is excluded due to too high flux densities and expected damage, for example at free-electron laser beamlines. Their availability became a bottleneck since the decommissioning of the grating manufacture facility at Carl Zeiss in Oberkochen. To resolve this situation a new technological laboratory was established at the Helmholtz Zentrum Berlin, including instrumentation from Carl Zeiss. Besides the upgraded ZEISS equipment, an advanced grating production line has been developed, including a new ultra-precise ruling machine, ion etching technology as well as laser interference lithography. While the old ZEISS ruling machine GTM-6 allows ruling for a grating length up to 170 mm, the new GTM-24 will have the capacity for 600 mm (24 inch) gratings with groove densities between 50 lines mm-1 and 1200 lines mm-1. A new ion etching machine with a scanning radiofrequency excited ion beam (HF) source allows gratings to be etched into substrates of up to 500 mm length. For a final at-wavelength characterization, a new reflectometer at a new Optics beamline at the BESSY-II storage ring is under operation. This paper reports on the status of the grating fabrication, the measured quality of fabricated items by ex situ and in situ metrology, and future development goals.
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Affiliation(s)
- F. Siewert
- Helmholtz Zentrum Berlin für Materialien und Energie, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - B. Löchel
- Helmholtz Zentrum Berlin für Materialien und Energie, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - J. Buchheim
- Helmholtz Zentrum Berlin für Materialien und Energie, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - F. Eggenstein
- Helmholtz Zentrum Berlin für Materialien und Energie, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - A. Firsov
- Helmholtz Zentrum Berlin für Materialien und Energie, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - G. Gwalt
- Helmholtz Zentrum Berlin für Materialien und Energie, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - O. Kutz
- Helmholtz Zentrum Berlin für Materialien und Energie, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - St. Lemke
- Helmholtz Zentrum Berlin für Materialien und Energie, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - B. Nelles
- DIOS GmbH, Bad Münstereifel, Schmittstraße 41, 53902 Bad Münstereifel, Germany
| | - I. Rudolph
- Helmholtz Zentrum Berlin für Materialien und Energie, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - F. Schäfers
- Helmholtz Zentrum Berlin für Materialien und Energie, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - T. Seliger
- Helmholtz Zentrum Berlin für Materialien und Energie, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - F. Senf
- Helmholtz Zentrum Berlin für Materialien und Energie, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - A. Sokolov
- Helmholtz Zentrum Berlin für Materialien und Energie, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - Ch. Waberski
- Helmholtz Zentrum Berlin für Materialien und Energie, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - J. Wolf
- Helmholtz Zentrum Berlin für Materialien und Energie, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - T. Zeschke
- Helmholtz Zentrum Berlin für Materialien und Energie, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - I. Zizak
- Helmholtz Zentrum Berlin für Materialien und Energie, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - R. Follath
- Helmholtz Zentrum Berlin für Materialien und Energie, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
- Paul Scherrer Institut, 5232 Villingen, Switzerland
| | - T. Arnold
- IOM – Leibniz Institut für Oberflächenmodifizierung eV, Permoserstrasse 15, 04318 Leipzig, Germany
| | - F. Frost
- IOM – Leibniz Institut für Oberflächenmodifizierung eV, Permoserstrasse 15, 04318 Leipzig, Germany
| | - F. Pietag
- IOM – Leibniz Institut für Oberflächenmodifizierung eV, Permoserstrasse 15, 04318 Leipzig, Germany
| | - A. Erko
- Helmholtz Zentrum Berlin für Materialien und Energie, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
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Abstract
Polymer melt infiltration is one of the feasible methods for manufacturing filter membranes out of carbon nanotubes (CNTs) on large scales. Practically, however, its process suffers from low yields, and the mechanism behind this failure is rather poorly understood. Here, we investigate a failure mechanism of polymer melt infiltration of vertical aligned (VA-) CNTs. In penetrating the VA-CNT interstices, polymer melts exert a capillarity-induced attractive force laterally on CNTs at the moving meniscus, leading to locally agglomerated macroscale bunches. Such a large configurational change can deform and distort individual CNTs so much as to cause buckling or breakdown of the alignment. In view of membrane manufacturing, this irreversible distortion of nanotubes is detrimental, as it could block the transport path of the membranes. The failure mechanism of the polymer melt infiltration is largely attributed to steric hindrance and an energy penalty of confined polymer chains. Euler beam theory and scaling analysis affirm that CNTs with low aspect ratio, thick walls and sparse distribution can maintain their vertical alignment. Our results can enrich a mechanistic understanding of the polymer melt infiltration process and offer guidelines to the facile large-scale manufacturing of the CNT-polymer filter membranes.
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Affiliation(s)
- Jakob Buchheim
- Nanoscience for Energy Technology and Sustainability, Department of Mechanical and Process Engineering, Eidgenössiche Technische Hochschule (ETH) Zürich, Tannenstrasse 3, Zürich CH-8092, Switzerland
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Buchheim J, Wyss RM, Shorubalko I, Park HG. Understanding the interaction between energetic ions and freestanding graphene towards practical 2D perforation. Nanoscale 2016; 8:8345-54. [PMID: 27043304 DOI: 10.1039/c6nr00154h] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We report experimentally and theoretically the behavior of freestanding graphene subjected to bombardment of energetic ions, investigating the capability of large-scale patterning of freestanding graphene with nanometer sized features by focused ion beam technology. A precise control over the He(+) and Ga(+) irradiation offered by focused ion beam techniques enables investigating the interaction of the energetic particles and graphene suspended with no support and allows determining sputter yields of the 2D lattice. We found a strong dependency of the 2D sputter yield on the species and kinetic energy of the incident ion beams. Freestanding graphene shows material semi-transparency to He(+) at high energies (10-30 keV) allowing the passage of >97% He(+) particles without creating destructive lattice vacancy. Large Ga(+) ions (5-30 keV), in contrast, collide far more often with the graphene lattice to impart a significantly higher sputter yield of ∼50%. Binary collision theory applied to monolayer and few-layer graphene can successfully elucidate this collision mechanism, in great agreement with experiments. Raman spectroscopy analysis corroborates the passage of a large fraction of He(+) ions across graphene without much damaging the lattice whereas several colliding ions create single vacancy defects. Physical understanding of the interaction between energetic particles and suspended graphene can practically lead to reproducible and efficient pattern generation of unprecedentedly small features on 2D materials by design, manifested by our perforation of sub-5 nm pore arrays. This capability of nanometer-scale precision patterning of freestanding 2D lattices shows the practical applicability of focused ion beam technology to 2D material processing for device fabrication and integration.
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Affiliation(s)
- Jakob Buchheim
- Nanoscience for Energy Technology and Sustainability, Department of Mechanical and Process Engineering, Eidgenössische Technische Hochschule (ETH) Zürich, Tannenstrasse 3, CH-8092 Zürich, Switzerland.
| | - Roman M Wyss
- Nanoscience for Energy Technology and Sustainability, Department of Mechanical and Process Engineering, Eidgenössische Technische Hochschule (ETH) Zürich, Tannenstrasse 3, CH-8092 Zürich, Switzerland.
| | - Ivan Shorubalko
- Laboratory for Reliability Science and Technology, Empa (Swiss Federal Laboratories for Materials Science and Technology), Überlandstrasse 129, CH-8600 Dübendorf, Switzerland.
| | - Hyung Gyu Park
- Nanoscience for Energy Technology and Sustainability, Department of Mechanical and Process Engineering, Eidgenössische Technische Hochschule (ETH) Zürich, Tannenstrasse 3, CH-8092 Zürich, Switzerland.
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Siewert F, Buchheim J, Zeschke T, Störmer M, Falkenberg G, Sankari R. On the characterization of ultra-precise X-ray optical components: advances and challenges in ex situ metrology. J Synchrotron Radiat 2014; 21:968-75. [PMID: 25177985 PMCID: PMC4151678 DOI: 10.1107/s1600577514016221] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Accepted: 07/11/2014] [Indexed: 05/26/2023]
Abstract
To fully exploit the ultimate source properties of the next-generation light sources, such as free-electron lasers (FELs) and diffraction-limited storage rings (DLSRs), the quality requirements for gratings and reflective synchrotron optics, especially mirrors, have significantly increased. These coherence-preserving optical components for high-brightness sources will feature nanoscopic shape accuracies over macroscopic length scales up to 1000 mm. To enable high efficiency in terms of photon flux, such optics will be coated with application-tailored single or multilayer coatings. Advanced thin-film fabrication of today enables the synthesis of layers on the sub-nanometre precision level over a deposition length of up to 1500 mm. Specifically dedicated metrology instrumentation of comparable accuracy has been developed to characterize such optical elements. Second-generation slope-measuring profilers like the nanometre optical component measuring machine (NOM) at the BESSY-II Optics laboratory allow the inspection of up to 1500 mm-long reflective optical components with an accuracy better than 50 nrad r.m.s. Besides measuring the shape on top of the coated mirror, it is of particular interest to characterize the internal material properties of the mirror coating, which is the domain of X-rays. Layer thickness, density and interface roughness of single and multilayer coatings are investigated by means of X-ray reflectometry. In this publication recent achievements in the field of slope measuring metrology are shown and the characterization of different types of mirror coating demonstrated. Furthermore, upcoming challenges to the inspection of ultra-precise optical components designed to be used in future FEL and DLSR beamlines are discussed.
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Affiliation(s)
- F. Siewert
- Institut für Nanometer Optik und Technologie, Helmholtz Zentrum Berlin, Albert-Einstein-Strasse 15, Berlin, Germany
| | - J. Buchheim
- Institut für Nanometer Optik und Technologie, Helmholtz Zentrum Berlin, Albert-Einstein-Strasse 15, Berlin, Germany
| | - T. Zeschke
- Institut für Nanometer Optik und Technologie, Helmholtz Zentrum Berlin, Albert-Einstein-Strasse 15, Berlin, Germany
| | - M. Störmer
- Centre for Material Research and Coastal Research, Helmholtz-Zentrum Geesthacht, Max-Planck-Strasse 1, Geesthacht 21501, Germany
| | - G. Falkenberg
- Photon Science, Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, Hamburg 22607, Germany
| | - R. Sankari
- MAX IV Laboratory, Lund University, Lund SE-22100, Sweden
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Celebi K, Buchheim J, Wyss RM, Droudian A, Gasser P, Shorubalko I, Kye JI, Lee C, Park HG. Ultimate permeation across atomically thin porous graphene. Science 2014; 344:289-92. [PMID: 24744372 DOI: 10.1126/science.1249097] [Citation(s) in RCA: 428] [Impact Index Per Article: 42.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
A two-dimensional (2D) porous layer can make an ideal membrane for separation of chemical mixtures because its infinitesimal thickness promises ultimate permeation. Graphene--with great mechanical strength, chemical stability, and inherent impermeability--offers a unique 2D system with which to realize this membrane and study the mass transport, if perforated precisely. We report highly efficient mass transfer across physically perforated double-layer graphene, having up to a few million pores with narrowly distributed diameters between less than 10 nanometers and 1 micrometer. The measured transport rates are in agreement with predictions of 2D transport theories. Attributed to its atomic thicknesses, these porous graphene membranes show permeances of gas, liquid, and water vapor far in excess of those shown by finite-thickness membranes, highlighting the ultimate permeation these 2D membranes can provide.
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Affiliation(s)
- Kemal Celebi
- Nanoscience for Energy Technology and Sustainability, Department of Mechanical and Process Engineering, Eidgenössische Technische Hochschule (ETH) Zurich, Sonneggstrasse 3, CH-8092 Zürich, Switzerland
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Yazdani N, Bozyigit D, Utke I, Buchheim J, Youn SK, Patscheider J, Wood V, Park HG. Enhanced charge transport kinetics in anisotropic, stratified photoanodes. ACS Appl Mater Interfaces 2014; 6:1389-1393. [PMID: 24467298 DOI: 10.1021/am405987t] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The kinetics of charge transport in mesoporous photoanodes strongly constrains the design and power conversion efficiencies of dye sensitized solar cells (DSSCs). Here, we report a stratified photoanode design with enhanced kinetics achieved through the incorporation of a fast charge transport intermediary between the titania and charge collector. Proof of concept photoanodes demonstrate that the inclusion of the intermediary not only enhances effective diffusion coefficients but also significantly suppresses charge recombination, leading to diffusion lengths two orders of magnitude greater than in standard mesoporous titania photoanodes. The intermediary concept holds promise for higher-efficiency DSSCs.
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Affiliation(s)
- Nuri Yazdani
- Nanoscience for Energy Technology and Sustainability, Department of Mechanical and Process Engineering, ETH Zürich ,, Sonneggstrasse 3, Zürich CH-8092, Switzerland
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