This title appears in the Scientific Report :
2023
High resolution and analytical transmission electron microscopy in a liquid flow cell via gas purging
High resolution and analytical transmission electron microscopy in a liquid flow cell via gas purging
Liquid phase electron microscopy (LPEM) based on sandwiched MEMS sample carriers provides the means toobserve time-resolved dynamics in a liquid state. Until now, LPEM has been widely used in materials science,energy and life science, providing fundamental insights into nucleation and growth, the dy...
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Personal Name(s): | Sun, H. (Corresponding author) |
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Park, Junbeom / Basak, Shibabrata / Beker, A. / van Omme, J. T. / Pivak, Y. / Garza, H. H. P. | |
Contributing Institute: |
Grundlagen der Elektrochemie; IEK-9 |
Imprint: |
2023
|
Conference: | Microscopy Conference 2023, Darmstadt (Germany), 2023-02-26 - 2023-03-02 |
Document Type: |
Poster |
Research Program: |
Power-based Fuels and Chemicals |
Publikationsportal JuSER |
Liquid phase electron microscopy (LPEM) based on sandwiched MEMS sample carriers provides the means toobserve time-resolved dynamics in a liquid state. Until now, LPEM has been widely used in materials science,energy and life science, providing fundamental insights into nucleation and growth, the dynamical evolution ofkey materials in batteries and fuel cells, as well as the 3D imaging of biomolecules [1]. Compared to liquid cellswithout a flowing function (such as static graphene pocket cells), liquid flow cells have obvious advantages.This includes the control of the liquid environment, the modulation of the effect of electron beam irradiation [2]and the integration of functional electrodes for heating or/and biasing. Due to the pressure difference betweenthe TEM column (~ 0 bar) and the enclosed liquid cell (~1 bar), the two membranes (silicon nitride with atypical thickness of ~50 nm) bulge outwards, resulting in a thick liquid layer, which can reach more than 1micrometer in the cell center region. Therefore, performing high resolution and analytical electron microscopystudies in a liquid flow cell comes with a multitude of challenges.Several strategies have been proposed to solve this issue, including (1) decreasing the membrane thickness orreplacing it with ultrathin materials e.g. graphene, h-BN, MoS2, etc. [3], (2) developing novel cellconfigurations, namely hole array patterns [4] and nanochannel [5], to avoid or decrease the bulging, (3)generating a gas bubble via electron beam irradiation [6,7], (4) generating a gas bubble via electrochemicalwater splitting [8] and (5) mitigating the window´s bulging by changing the pressure difference between the celland TEM column, either via an external pressure controller [9,10] or via the internal Laplace pressure [10].Those methods have been proven useful in high resolution and analytical electron microscopy studies in LPEM,however, there are also intrinsic limitations in each method.In this work, we propose a general and robust method to perform high resolution and analytical electronmicroscopy studies in a flow cell (the Stream Nano-Cell), which can be implemented during liquid heating orliquid biasing experiments. Thanks to the on-chip flow channel of the Stream Nano-Cell [11], the liquid in thefield of view can be removed by flowing gas (including inert gases to avoid problems with air sensitivity), whichis termed "purging". This purging method enables the acquisition of high-resolution TEM images, chemicalcomposition and valence analysis through energy-dispersive X-ray spectroscopy (EDX) mapping and ElectronEnergy-Loss Spectroscopy (EELS), respectively. In addition, the purging approach is both reversible andreproducible, which therefore enables the alternation between a full cell and a thin liquid configuration to studyliquid-thickness-dependent physical and chemical phenomena.References1.F. M. Ross. Science, 2015, 350, aaa9886.2.N. M. Schneider, et al. J. Phys. Chem. C, 2014, 118, 22373.3.G. Dunn, et al., ACS Nano, 2020, 14, 9637.4.S. Nagashima, et al. Nano Lett., 2019, 19, 10, 7000.5.M. N. Yesibolati, et al. Phys. Rev. Lett., 2020, 124, 065502.6.G. Zhu, et al. Chem. Commun. 2013, 49, 10944.7.U. Mirsaidov, et al. Soft Matter, 2012, 8, 7108.8.R. Serra-Maia, et al. ACS Nano 2021, 15, 10228.9.S. Keskin, et al. Nano Lett., 2019, 19, 4608.10.H. Wu, et al. Small Methods, 2021, 5, 2001287.11.A. F. Beker, et al. Nanoscale, 2020, 12, 22192. |