Introducing the Stream Liquid Supply System: An integrated solution offering unmatched flexibility

Introducing the Stream Liquid Supply System: An integrated solution offering unmatched flexibility

An interview with DENSsolutions Mechanical Engineer Alejandro Rozene about our latest addition to the Stream product line: the Liquid Supply System (LSS).

DENSsolutions introduces its latest solution: the Stream Liquid Supply System (LSS): an integrated solution designed to offer you ease-of-use, flexibility and reproducibility in your in situ liquid experiments. In this article, we interview our Mechanical Engineer Alejandro Rozene to learn all about the LSS, from what inspired its development, its unique capabilities and the many applications that will benefit from its creation.

What led to the development of the Stream Liquid Supply System?

“Our Liquid Phase Electron Microscopy (LPEM) solutions have been used by researchers around the world in a plethora of research fields, such as protein studies, battery research and molecular self-assembly. With our Stream system, users can fully control the microfluidic environment inside the Nano-Cell, our environmental MEMS sample carrier, while biasing or heating their sample. Considering the wide range of capabilities the system offers and the complexity of LPEM, Stream is quite the advanced system. This is precisely what inspired the next step in the innovation process: the development of an integrated solution designed to offer greater flexibility and ease-of-use. The Liquid Supply System (LSS) is a single scientific instrument that allows microscopists to carry out imaging experiments in fewer steps while introducing new features. The LSS is also designed to be the basic unit of a modular system that can be configured for different research applications.” 

What are the main benefits of the LSS for users?

“The introduction of the LSS to the Stream product line brings forth numerous advantages for your in situ liquid experiments, including greater flexibility, reliability and reproducibility. These benefits are detailed below:

1) Ease of use: Thanks to the clever architecture of the LSS, particularly the moveable base, you can easily relocate, store and set it up in various locations. It is also possible to control the microfluidic environment of the Nano-Cell and to apply different stimuli using a single interface in Impulse, our in situ experiment control and automation software. All of the sensor data is collected centrally. The LSS therefore simplifies the LPEM workflow and allows you to shift the focus from the hardware to the imaging experiment. This will potentially open the door to more elaborate experimental workflows.

2) High resolution imaging and meaningful analytical analysis: It is widely known that LPEM suffers from limited resolution caused by the thickness of the liquid layer inside the sample chamber. Even a 500 nm liquid layer can limit imaging resolution. With the LSS, the capability of controllable and inert gas purging is introduced. This means that you can easily displace the liquid in the Nano-Cell and effortlessly cycle between dry and liquid environments. This can be done with air or with an inert gas for air-sensitive samples. Via purging, you can easily get rid of excess liquid in the sample, thereby allowing you to achieve high resolution imaging, image in electron diffraction mode and perform spectroscopy techniques: EDS and EELS.

3) Reliable and reproducible results: The components of the LSS, such as the inlet and outlet pressure-based pumps as well as the liquid flow meter, introduce an unprecedented level of control during your liquid phase microscopy experiments. The LSS offers the unique ability to actively measure the liquid flow, making it possible for you to compare results from different experiments. Moreover, this means that you can easily detect potential clogs in the system and act fast, allowing you to spend your TEM time efficiently and effectively. Ultimately, the combination of our LSS and unique Nano-Cell design, having an on-chip inlet and outlet, enables the liquid delivery to be both reliable and reproducible with a success rate of more than 95%.”

Which applications will benefit most from the LSS?

“The LSS is beneficial for any researcher who wants to use LPEM to observe hydrated samples, matter suspended in liquid or liquid itself in a dynamic environment. Some of the many fields that will benefit from the system include:

  1. Life Science: DNA imaging, biomineralization, cell imaging and protein studies
  2. Electrochemistry: studies of aqueous electrolytes and electrocatalysis
  3. Material Science: studies of nanoparticle formation, self-assembly and growth

These are just a few examples of the several fields that can benefit from the Stream system. Furthermore, the door is open to any researcher who may want to exploit the unique capabilities of the LSS for any liquid-based study outside of the TEM.”

What kind of challenges were tackled during development?

“The LSS is a state-of-the-art scientific instrument. As with any other mechatronic development, integrating the sensing, actuating and microfluidic components into a single, robust machine was in itself a challenge. Also, our market is especially demanding since the users of this instrument already work with some of the most advanced equipment out there, which undoubtedly sets the bar very high. However, it was a very enjoyable experience thanks to the incredible teamwork and collaboration of our MEMS Project Manager, Tijn van Omme, and our Software Developer, Emil Svensson, as well as our manufacturing partners.”

What is the compatibility of the LSS?

“The LSS is an integral part of our Stream product line. It is therefore fully compatible with the modular Stream sample holder, the Stream liquid biasing and liquid heating Nano-Cells, as well as with Impulse. With regards to the microscopes, compatibility is given by the holder type. We currently offer compatibility with JEOL and Thermo Fisher Scientific microscopes.”

Has the LSS already been installed?

“Yes, the Liquid Supply System has been installed at the University of Alberta Nanofabrication and Characterization Facility (nanoFAB) in Canada. The nanoFAB is a national, open-access training, service, and collaboration centre, focused on academic and industrial applications in micro- and nanoscale fabrication and characterization. The installation was carried out by our MEMS Project Manager, Tijn van Omme, with the support of our close distributor Colt Murray from Nanoscience Instruments. It is the first of several installations planned in the upcoming months.”

From left to right: XueHai Tan, Colt Murray, Tijn van Omme and Haoyang Yu

Read more about the LSS:

 

Receive a quotation for Stream:

Subscribe to our newsletter to stay up-to-date with the latest in situ microscopy news.

Unraveling the dynamic behavior of zinc electrodes in aqueous electrolytes using our Stream system

Unraveling the dynamic behavior of zinc electrodes in aqueous electrolytes using our Stream system

Scientists are able to observe for the first time using in situ TEM the morphology and phase evolution of zinc anodes during zinc dissolution and deposition in aqueous electrolytes.

Original article by Yongfeng Huang, Qingqing Gu, Zhanglong Guo, Wenbao Liu, Ziwen Chang, Yuefeng Liu, Feiyu Kang, Liubing Dong, Chengjun Xu

Marc Willinger TOC 1200x628

Metallic zinc is a widely used electrode material for aqueous rechargeable zinc-ion batteries (ZIBs) due to its high theoretical capacity, low redox potential, natural abundance and low cost. Despite these valuable benefits, zinc electrodes suffer from short cycling stability due to many factors such as the growth of zinc dendrites as well as corrosion. Little is known about the underlying reasons for the failure of zinc anodes on a deeper level. Indeed, the use of in situ transmission electron microscopy can serve as a means to bridge this gap in knowledge, unraveling the morphological evolution of zinc anodes during zinc dissolution and deposition in aqueous electrolytes. 

In recent research performed at the DICP-DENS Microscopy Centre by Dr. Yuefeng Liu from the Dalian Institute of Chemical Physics, Yongfeng Huang from Tsinghua University, and many more collaborators, they were able to obtain a deep understanding of the stripping/plating behaviors of zinc in various aqueous electrolytes using the DENSsolutions Stream system. Specifically, the researchers investigated the effects of adding Mn²⁺ and CF₃SO₃⁻ in zinc-salt aqueous electrolytes on the zinc plating/stripping behavior. This work not only sheds light on the mechanism of zinc anodes during zinc dissolution/deposition processes in aqueous electrolytes, but also provides effective strategies to achieve long-term stable rechargeable zinc-ion batteries (ZIBs). 

Three aqueous electrolytes

As the high reversibility of zinc anodes is a prerequisite for large- scale applications of ZIBs and ZHSs, many efforts have been dedicated to achieve long-term stable zinc anodes. One effective way to stabilize and acquire dendrite-free zinc anodes is by introducing additives in aqueous electrolytes. In previous studies, it was found that the addition of Mn²⁺ in the form of MnSO₄ to a ZnSO₄ aqueous electrolyte can actually suppress the dissolution of the MnO₂ cathode. Similarly, in comparison to a ZnSO₄ electrolyte, a Zn(CF₃SO₃)₂ electrolyte is far more effective in achieving better electrochemical performance of many ZIB systems.

For these reasons, aside from a pure ZnSO₄ electrolyte, ZnSO₄/MnSO₄ and Zn(CF₃SO₃)₂ are commonly used aqueous electrolytes for ZIBs. Despite this, zinc plating/stripping behaviors in ZnSO₄/MnSO₄ and Zn(CF₃SO₃)₂ and their effects on electrochemical stability of metallic zinc anodes are unknown. In this study, the researchers combine operando TEM and electrochemical analysis to unravel the zinc stripping/plating behaviors in the three aqueous electrolytes detailed above (ZnSO₄, ZnSO₄/MnSO₄ and Zn(CF₃SO₃)₂). In the following sections, in situ TEM images and videos of the zinc stripping/plating process in the three different electrolytes are shown.

1) Zinc plating/stripping process in a ZnSO₄ electrolyte

The researchers first constructed a micro zinc-ion battery inside the Stream holder, allowing them to monitor the zinc plating/stripping processes using the system’s on-chip flow channel. After assembling the Stream Nano-Cell and leak-testing it, the researchers were then able to flow the electrolytes into the liquid cell, using the pressure-based liquid pump to fully control the rate of the flow. 

Next, the researchers set out to observe the zinc stripping/plating behavior in a pure ZnSO₄ aqueous solution. In Figure 1 below, the in situ TEM images detailing the zinc plating and stripping process at different times in 2 M ZnSO₄ are shown. During the zinc plating process exhibited in Figure 1a–d, the thickness of zinc deposited on the platinum substrate increases. Simultaneously, dendrite-like structures form and develop gradually. This confirms the dendrite issue of metallic zinc electrodes in the 2 M ZnSO₄ electrolyte, which leads to a short-circuit occurrence. After this, the zinc stripping process occurs, which is demonstrated in Figure 1d–f. During this process, it is observed that the deposited zinc is unable to fully strip away from the platinum substrate and dissolve into the electrolyte under the same charge and discharge time conditions. As a result, dead zinc is generated (see Figure 1f).

Figure 2: Marc Willinger

Figure 1: In-situ TEM images of zinc plating/stripping on the surface of Pt working electrode in 2 M ZnSO₄ electrolyte at different times: (a) 0 s, (b) 3 s, (c) 10 s, (d) 28 s, (e) 80 s and (f) 261 s.

Electrolytes of high concentrations are generally not conducive for monitoring zinc stripping/plating behaviors using in situ TEM, as they can block out the liquid inlet hole of the holder. Due to this, along with the valuable insights that further investigating the effect of concentration on dendrite growth can provide, the ZnSO₄ electrolyte was diluted from 2 M to 20 mM. The researchers then observed the zinc stripping/plating process in the 20 mM ZnSO₄ aqueous electrolyte. The in situ TEM images and corresponding movie detailing this process can be seen below in Figure 2 and Video 1, respectively. 

The zinc stripping/plating process was controlled using the cyclic voltammetry (CV) technique at 20 mV/s. Figure 2g shows the corresponding CV curve, where the red dots marked as a–f correspond to the states in Figure 2a–f. At 71s (see Figure 2b), the researchers observed that the visible zinc particles in the electrolyte, as well as the dense dispositioned zinc and the zinc dendrites (marked in green) on the surface of the Pt substrate occur at the same. Between 76s–95s (Figure 2c-d), they noticed that more zinc was plating on the platinum surface, with the potential ranging from − 1.41 V to − 1.1 V. Next, the process of zinc dissolution occurs, where the zinc frontier line is observed to shrink back to area II at 114s (Figure 2e) and to the edge of the Pt substrate at 144s (Figure 2f). It is observed that the dendrite is still not completely removed when the potential returns to 0 V. Conclusively, although reducing the concentration can slow down dendrite formation, it does not fully suppress it.

Figure 2: In-situ TEM images of zinc plating/stripping on the surface of Pt working electrode in 20 mM ZnSO₄ electrolyte at different times: (a) 0 s (b) 71 s, (c) 76 s, (d) 95 s, (e) 114 s and (f) 144 s. (g) CV curve of zinc stripping/plating process on the surface of Pt working electrode in 20 mM ZnSO4 electrolyte at a scan rate of 20 mV/s. (h) XRD pattern after zinc plating/stripping at Pt. (i) XPS result after zinc plating/stripping at Pt.

Video 1: Video of zinc plating/striping at the interface of Pt working electrode in 20 mM ZnSO₄ electrolyte.

2) Zinc plating/stripping process in a ZnSO₄/MnSO₄ electrolyte mixture

The next step for the researchers was to observe the zinc stripping/plating process in a ZnSO₄/MnSO₄ electrolyte mixture, as MnSO₄ additives in ZnSO₄ electrolytes can actually optimize the electro-chemical stability of metallic zinc electrodes. They first added 5 mM MnSO₄ to the 20 mM ZnSO₄ aqueous electrolyte. The in situ TEM images and corresponding movie detailing the resulting zinc plating/stripping process can be seen below in Figure 3 and Video 2, respectively. 

Figure 3a–d depicts the zinc plating process, in which Mn spherical particles appear and gradually increase in size. At 124s (see Figure 3e), the zinc stripping process starts to occur, and these spherical particles in the electrolyte begin to disintegrate and finally disappear at 259s (see Figure 3i). Aside from the spherical particles in the electrolyte, a visible amount of deposited zinc (marked in green in Figure 3e) appears on the Pt working electrode. Notably, the sphere species, both in the electrolyte and also on the surface of the Pt substrate, disintegrate. This results in the further precipitation of zinc and leads to the increased thickness of zinc. Interestingly, zinc dendrites were not observed to form in the ZnSO₄/MnSO₄ electrolyte mixture, unlike in the pure ZnSO₄ electrolyte. This directly suggests that the Mn²⁺ additive is indeed beneficial for suppressing the formation of zinc dendrites.

Figure 3: Zinc stripping/plating behaviors in 20 mM ZnSO₄ + 5 mM MnSO₄ electrolyte at different times: (a) 0 s (initial state), (b) 60 s (c) 69 s, (d) 119 s, (e) 124 s, (f) 177 s, (g) 199 s, (h) 238 s and (i) 259 s. (j) Cyclic voltammogram curve of Zn plating and striping at the interface of Pt working electrode at a scan rate of 20 mV/s, the red dots are assigned to Figure a-i, (k) XRD pattern after zinc plating/stripping at Pt (CaCO₃ is from the XRD bonding adhesives), and (l) E-pH diagram of Mn.

Video 2: Video of zinc plating/striping at the interface of Pt working electrode in the 20 mM ZnSO₄ + 5 mM MnSO₄ electrolyte.

3) Zinc plating/stripping process in a Zn(CF₃SO₃)₂ electrolyte

Finally, the researchers set out to explore the zinc plating/stripping process in a 20 mM Zn(CF₃SO₃)₂ electrolyte. The in situ TEM images and corresponding movie detailing the resulting zinc plating/stripping process in this electrolyte is shown in Figure 4 and Video 3, respectively. The zinc plating process is depicted in Figure 4a–d, where particle-like zinc uniformly deposits on the surface of the Pt substrate, and the thickness of the deposited zinc layer increases. Here, no zinc dendrites form during the plating process. At 175s (see Figure 4e), the zinc stripping process starts, and the deposited zinc particles on the Pt substrate gradually dissolve into electrolyte. Finally, at 240s (see Figure 4f), all zinc particles disappear, demonstrating the high reversibility of zinc deposition/dissolution in the Zn(CF₃SO₃)₂ electrolyte. Importantly, the deposition of zinc on the Pt substrate in the Zn(CF₃SO₃)₂ electrolyte is more uniform and homogeneous than that in the ZnSO₄ electrolyte and ZnSO₄/MnSO₄ electrolyte mixture.

Figure 4: Zinc stripping/plating behaviors in 20 mM Zn(CF₃SO₃)₂ electrolyte at different times: (a) initial, 1.0 V (b) 124 s, -1.48 V, (c) 130 s, -1.40 V, (d) 138 s, -1.24 V, (e) 175 s, -0.40 V, (f) 240 s, 0.80 V, (g) Cyclic voltammogram curve at the scan rate of 20mV/s about Zn plating and striping at the interface of Pt working electrode in 20 mM Zn(CF₃SO₃)₂ electrolyte, the red dots are assigned to Figure a-f (h) XRD pattern after zinc plating/stripping at Pt (CaCO3 is from the XRD bonding adhesives). (i) SEM image after Zn plating on Pt.

Video 3: Video of zinc plating/striping at the interface of Pt working electrode in the 20 mM Zn(CF₃SO₃)₂ electrolyte.

Conclusion

This paper provides a novel understanding of the failure process of metallic zinc electrodes in a ZnSO₄ electrolyte, as well as the effects and acting mechanism of Mn²⁺ in the ZnSO₄/MnSO₄ electrolyte mixture and CF₃SO₃⁻ in the Zn(CF₃SO₃)₂ electrolyte on the zinc plating/stripping behavior. These deep-level insights serve to close the gap in our understanding of how we can create long-term stable ZIBs with metallic zinc anodes and optimal aqueous electrolytes, beneficial for several critical applications, including large-scale energy storage and portable electronic applications. The discovery of such findings could not be possible without the application of in situ characterization techniques, for which our Stream system has proved to be remarkably effective.

Original article:

Discover our Stream solution:

Discover more publications made possible by Stream:

Thomas article feature image

Scientists develop a novel approach to generate extreme thermal gradients using our Wildfire Nano-Chip

Via a simple modification to our Wildfire Nano-Chip, scientists show that extreme thermal gradients across a TEM specimen can be generated.

Subscribe to our newsletter to stay up-to-date with the latest in situ microscopy news.

DENSsolutions has installed yet another Stream system in Germany at Forschungszentrum Jülich

DENSsolutions has installed yet another Stream system in Germany at Forschungszentrum Jülich

DENSsolutions Installing South Korea's second Stream system at Seoul National University

From left to right: Andreas Körner and Dr. Andreas Hutzler

We are proud to announce that DENSsolutions has installed yet another Stream system in Germany at the esteemed Forschungszentrum Jülich, one of the largest interdisciplinary research centres in Europe. In this article, we interview Dr. Andreas Hutzler, the new head of the TEM lab in the Helmholtz Institute Erlangen-Nürnberg for Renewable Energy (HI ERN) at Forschungszentrum Jülich, to learn more about their advanced microscopy facility, its research direction, as well as how our Stream system is advancing their research.

Can you tell me more about the microscopy facility at HI ERN?

“The Helmholtz Institute Erlangen-Nürnberg for Renewable Energy (HI ERN) is part of the Forschungszentrum Jülich. It specializes in providing crucial research on technologies needed to utilize renewable energies in the decades to come. Our research is centered around fuel cells, electrolyzers and hydrogen storage. The institute was founded in 2013 and has been growing ever since. In 2021, its new research building was inaugurated, hosting the space for a new transmission electron microscope, the Talos F200i from Thermo Fisher Scientific. This tool provides in-house structural analysis on the nanoscale for catalysts, support systems and membranes.”

What type of applications are the users at HI ERN using the Stream system for?

“Our goal is to study electrochemical processes taking place on electrode and catalyst surfaces within electrolyzers and fuel cells down to the atomic scale. We aim to understand which reactions take place, and which conditions enhance the performance of the cells or disintegrate the structures involved.

In order to understand this, we consider beam-induced effects onto the solution chemistry we investigate. For this, we utilize a comprehensive radiolysis model for unraveling the influence of electron irradiation onto the sample and compare the results to non-biased experimental observations. Once this is understood, we continue with analyzing dynamic processes at the nanoscale to gain insights into reaction pathways and degradation mechanisms in P2X and X2P applications.”

What particular features of the DENSsolutions Stream solution attracted you to the system?

“In order to understand observable processes and their correlated chemistry, it is necessary to accurately tune experimental conditions while operating the system. The ability of the Stream system to flexibly adjust pressure, flux, temperature and potential allows to run a manifold of experiments in a wide parameter space. This is needed in order to verify the stability of our reaction kinetic models and for testing electrolysis at borderline conditions. Before, the structures could only be studied after the reaction has taken place. But the ability to directly observe dynamic processes on-site in real time gives valuable insights in the chemistry at hand.”

Can you tell me about the grant that was won to acquire the system?

“One of our key research interests is the development of new methods for characterizing fundamental and applied processes in electrocatalysis relevant to electrochemical energy conversion. After establishing identical-location TEM (IL-TEM) for energy applications and with the start of my team, a new transmission electron microscope as well as equipment needed for in situ liquid-phase TEM was funded by and installed at HI ERN. This particular toolbox will be a great asset for the nanoanalysis of electrochemical processes in my team which will enable unique insights in energy research.”

In your experience so far, how have you found the Stream system?

“The modular architecture of the Stream system enables a very versatile applicability without risking leakage or cross-contaminations. The performance of LP-TEM is considerably enhanced due to the controllability of liquid flow, the ever-present window bulging via the utilization of a novel chip design as well as a differential pumping system as a standard. Moreover, DENSsolutions came forward with providing non-standard solutions in order to provide compatibility with other setups at our institute.”

DENSsolutions Prof. Jungwon Park
Dr. Andreas Hutzler
Head of the Transmission Electron Microscopy lab| HI ERN, Forschungszentrum Jülich

Dr. Andreas Hutzler is the new head of the Transmission Electron Microscopy lab at HI ERN, PI of multiple projects at HI ERN and university and is currently setting up a team for nanoanalysis of electrochemical processes. His research interests mainly focus on methodological aspects of LP-TEM and its application in electrochemical energy conversion.

Discover Dr. Andreas Hutzler’s publications:

Learn more about Stream:

Discover publications made possible by Stream:

Subscribe to our newsletter to stay up-to-date with the latest in situ microscopy news.

Installing South Korea’s second Stream system at Seoul National University

Installing South Korea’s second Stream system at Seoul National University

DENSsolutions Installing South Korea's second Stream system at Seoul National University

The team at SNU (From left to right) Prof Jungwon Park, Back Kyu Choi, Minyoung Lee and Junyoung Heo.

With the second ever installation of a Stream LPEM Solution in South Korea, we get an insider’s look at the microscopy laboratory at the Seoul National University. We interviewed Prof Jungwon Park from the National Center for Inter-University Research Facilities to find out how our solutions will benefit their research when investigating synthetic mechanisms of inorganic nanocrystals.

Can you tell us a bit about the microscopy facility at Seoul National University SNU?

Seoul National University has a shared research facility called NCIRF (National Center for Inter-University Research Facilities) that has specialities in various fields of analysis, such as organic, inorganic, surface analysis, and x-ray techniques. NCIRF also has a special team in electron microscopy, which provides SEM, TEM, and other pretreatment equipment including FIB and Nanomill.

This shared facility was established around 30 years ago. Recently, two spherical aberration-corrected TEM and STEM, JEM-ARM200F, were installed, providing atomic-resolution electron microscopy images. Also, in our own center, the Institute for Basic Science Center for Nanoparticle Research, we have our own JEOL JEM-2100F TEM in our building which is utilized routinely for a lot of in situ EM studies.

What type of applications are your users interested in with regards to the Stream system installed?

Our users are interested in various nanocrystal dynamics. Regarding the Stream system, we are expecting to investigate the synthetic mechanism of colloidal inorganic nanocrystals by changing the liquid cell temperature and injected precursor solution. Also, we are planning to investigate transformation phenomena of colloidal nanocrystals in various liquid environments. Moreover, we are expecting to observe polymers or proteins in liquid, and their stimuli-responsive reactions using the Stream system.

What particular features of the DENSsolutions Stream solution attracted you to the system?

When it comes to liquid cell TEM experiments, it is crucial to ensure that a controlled amount of liquid is injected to the desired position, while minimizing the decrease in spatial resolution of TEM stemming from the window bulging effect. In this sense, the Stream system by DENSsolutions was quite attractive to us.
With ensured liquid flow from Nano-cell design, controlled injection of liquid, as well as mitigated window- bulging originating from the pressure-based liquid pump, and also along with the liquid heating control system, the Stream solution seemed to help us to design various in situ liquid cell systems which were unachievable with other in situ holders.

In your experience so far, how have you found the Stream system?

At first, the Stream system was quite complicated to us since a lot of elaborate systems were installed. But soon we realized that it was much simpler than it seemed. The method to assemble the Stream holder was easy compared to other liquid cell TEM holders, and the way to control the injection solution was straightforward. And since a lot of O rings are used to encapsulate the Nano-cell, the holder seems to be very stable without leakage problems while operating the TEM. Also, the heating control software was upgraded from the Wildfire version, making it much easier to use the program.

DENSsolutions Prof. Jungwon Park

Jungwon Park, Ph.D
Associate Professor | Seoul National University

Jungwon Park received his B.S. degree from the Department of Chemistry, POSTECH, South Korea, in 2003, and his Ph.D. degree from the Department of Chemistry, University of California, Berkeley, in 2012. After a post-doc with the School of Engineering and Applied Sciences, Harvard University, he started a faculty position with the School of Chemical and Biological Engineering, Seoul National University, in 2016, and he currently serves as an associate professor jointly affiliated with the Center for Nanoparticle Research, Institute for Basic Science (IBS). His research areas include the in-situ study of nanomaterials, liquid-phase TEM, phase transitions, interface chemistry, and low-dimensional materials.

Learn more about Stream:

Discover Jungwon Park’s publications:

Discover publications made possible by Stream:

Do you want to receive great articles like this in your mailbox? Subscribe to our newsletter.

Installing the first Stream system in Singapore at the Nanyang Technological University

Installing the first Stream system in Singapore at the Nanyang Technological University

Standing next to the recently installed Stream system: from left, Dr. Anastasia Shebanova, Dr. Martial Duchamp and Jeffrey George from the Nanyang Technological University

We are happy to announce that the first ever Stream system in Singapore has recently been installed! For this event we interviewed Dr. Martial Duchamp from the School of Materials Science and Engineering at the Nanyang Technological University (NTU) in Singapore. In this interview, we discussed NTU’s advanced microscopy facility and the various applications that LPEM users are interested in, as well as how our Stream system has greatly benefited their research.  

Can you tell me a bit about the microscopy facility at the Nanyang Technological University?

The Nanyang Technological University has a shared microscopy facility called FACTS (Facility for Analysis Characterization Testing & Simulation) that specializes in characterization in the field of electron microscopy and x-ray techniques. FACTS provides state-of-the-art electron microscopes and X-ray instruments as well as the expertise to operate them to all of NTU and beyond.

This shared facility was created around 20 years ago. Four years ago, we had an extension of the facility, and got two aberration-corrected transmission electron microscopes as well as a new building where these TEMs were installed. The first TEM is a JEOL JEM-ARM200F, and the second is the JEOL JEM-GrandARM that is both probe- and image-corrected. Moreover, we have some local technicians and engineers who take care of these microscopes and make sure the facility is running well.

What type of applications are Stream users at the facility interested in?

Users of the facility are interested in a wide range of applications. In regards to LPEM users, we are using the DENSsolutions Stream system to study the liquid-liquid phase separation (LLPS) aspect of biological systems. Specifically, we are interested in the process called coacervation, which involves starting with a mixed phase of polymer or proteins dispersed in a solvent, and by changing certain conditions like the pH, temperature or salt concentration you can go from this diluted phase to a solid phase via phase separation. We are particularly interested in phase separation in order to understand how we go from these diluted solutions of drugs or proteins to solid matter.

Aside from liquid TEM, I am also interested in using in situ and operando TEM to observe 2D materials and the evolution of these materials versus temperature, as well as solar cells and batteries.

Can you tell us who won the grant to acquire the Stream system?

Associate Professor Ali Miserez, the lead PI of the project titled “Phase Separation-Regulated Life, In and Outside of Cells”, was awarded the Ministry of Education (MOE) Tier 3 grant worth 8.5 million Singaporean dollars. This research programme aims to closely integrate the tools of cell biology and colloidal biochemistry with the framework developed in the materials science of polymer science, soft matter, and complex fluids. The goal is to unravel LLPS-mediated functional organization across multiple biological length scales. Part of this grant was used to acquire the Stream system.

This 5-year project started last summer, and we are just starting to employ new researchers. In fact, some students already started a couple months ago and we expect to have some more people joining.

What particular features of Stream attracted you to the system?

For our experiments, it was essential to find a way to control the flux of the liquid within the liquid cell in order to look at reactions or processes occurring on the location of the electron beam. This is something we were unable to do with previous generations of holders and chips. The DENSsolutions Stream system is the only system that allows you to completely control the liquid flux. This unique capability is what intrigued us most about the system.

Moreover, as a result of the Nano-cell’s special inlet-outlet design, we are also able to fully control the pressure and liquid thickness. Other features that we found very attractive include the control systems like the heating control unit and the pressure-based pump, which are considerably more elaborate compared to what we had in the past.

In your experience so far, how have you found the Stream system?

The assembly in regards to the closing of the cell is quite straightforward, and so far we have not had any leakage issues. Just by closing the cell, it becomes airtight, which is a great advantage of the system. Moreover, what I really appreciate about the system is the ability to have complete control over the flow of the liquid.

Dr. Mihaela Albu

Dr. Martial Duchamp
Assistant Professor | Nanyang Technological University

Dr. Martial Duchamp is an Assistant Professor in the school of Materials Science and Engineering at the Nanyang Technological University in Singapore. His research interests include the development of innovative operando TEM methods for application to solar cells, batteries and fuel cells devices, as well as obtaining a fundamental understanding of 2D materials to reveal their unprecedented electrical properties at local scale.

Learn more about Stream:

Discover Martial Duchamp’s publications:

 

Discover publications made possible by Stream:

Do you want to receive great articles like this in your mailbox? Subscribe to our newsletter.

Achieving mass transport control with the award-winning Stream system

Achieving mass transport control with the award-winning Stream system

The on-chip flow channel of the Stream system allows for full control over pressure, flow rate, liquid thickness and electric potential

Original article by Anne France Beker, Hongyu Sun, Mathilde Lemang, Tijn van Omme, Ronald G. Spruit, Marien Bremmer, Shibabrata Basak and  H. Hugo Pérez Garza

The liquid phase transmission electron microscopy (LPTEM) community faces numerous challenges when performing in situ electrochemical studies inside the TEM. From a lack of control over the flow and liquid thickness, to limited experimental flexibility and reproducibility, these challenges have posed considerable limitations on research. As a result, DENSsolutions has developed an in situ LPTEM solution that addresses each and every one of these challenges – the Stream system. Due to its unique on-chip flow channel design, users can effectively control experimental conditions such as pressure, flow rate, liquid thickness, electrical potential and bubbles. STEM videos are shown below to demonstrate these advantages and visualize the in situ growth of copper with multiple morphologies.

Because you can independently control the pressure at the inlet and outlet of the Stream Nano-Cell, you can control the absolute pressure in the microfluidic channel. This state-of-the-art design consequently gives you full control over the flow and the bulging of the windows, and therefore the liquid thickness. As a result, spatial resolution is improved, enabling meaningful electron diffraction and elemental mapping in liquid. You can accurately define the mass transport and control the electric potential, granting you complete access to the full kinetics of the reaction.

The in situ LPEM study

In order to exhibit the benefits of the system, copper dendrites were grown and characterized in situ. After the electrodeposition of the copper, EELS and EDS characterization were performed with copper inside the viewing area. Furthermore, high resolution images and diffraction patterns of the grown copper dendrites were recorded using the TEM.

Removal of beam-induced species

A major issue when performing LPTEM experiments with an electrolyte is the undesired influence of the electron beam. In this experiment, the electron beam interacts with the copper electrolyte. However, because you can control the flow of the liquid, you can remove or flush away any unwanted beam-induced species from the region of interest (i.e. window, sample or electrodes). This is displayed in the STEM recording below with the flow moving from right to left.

STEM movie showing debris being flushed

Bubble dissolution

It is important in LPTEM to assure that the cell stays wet. However, when bubbles form, the cell starts to dry out. The Stream system was developed with this in mind, offering a solution to this challenge. Specifically, because you can control the absolute pressure in the microfluidic channel, you can remove unwanted gas bubbles by setting the pressure high. At higher pressures, the size of the bubble decreases until it disappears and vice versa. The dissolution of a bubble that was formed during this copper experiment is shown in the STEM video below.

STEM movie showing bubble dissolution

In situ growth of copper dendrites

The growth and stripping of copper was completed a few times via cyclic voltammetry. The cycles begin with copper reduction, corresponding to the growth of the copper dendrites. Next, oxidation takes place, corresponding to the copper dendrites being stripped. Interestingly, you can see in the STEM video below that after reduction, the dendrites are thicker whereas after oxidation, the dendrites become much thinner.

STEM movie showing 5 cycles of copper growth and etching

Liquid thickness control 

In order to perform high resolution imaging, it is important in LPTEM that the liquid thickness is kept low. Aside from high resolution imaging, controlling the liquid thickness is extremely important when performing analytical techniques like EDS, EELS and electron diffraction. Ideally, the liquid should be limited below the beam broadening, which is normally expected to happen around 500nm of liquid thickness. With this in mind, we designed our Nano-Cell such that the thickness stays below the beam broadening threshold based on the spacer thickness and the maximum bulging of the windows. In the figures below, the elemental mapping and electron diffraction of the electrodeposited copper are presented. 

Elemental mapping - Anne article

EDX elemental mapping showing the spatial distribution of b) the copper dendrites and c) the platinum electrode 

Electron diffraction Annette article

TEM image of the copper dendrites on the electrode in e) and the corresponding SAED patterns in liquid phase in f)

Complete flow control

Controlling the flow also has other important advantages that are expanding possibilities in research. Namely, the ability to manipulate the flow rate allows you to control the morphology. You can see in the STEM image below that when flow is applied, the copper grows in a continuous layer with more copper being deposited. On the other hand, without flow, the copper nuclei grow isolated. This is direct proof that the unique flow-control feature of the system allows you to control the kinetics of an electrochemical reaction.

Morphology of copper with and without flow using the Stream system

Conclusively, this research highlights the unique capabilities of the award-winning Stream system, proving its potential to enable and boost research in various application fields, ranging from battery research and fuel-cells to corrosion and electrocatalysis.

Original article:

More about Stream:

Do you want to receive great articles like this in your mailbox? Subscribe to our newsletter.