Uppsala University in Sweden expands its TEM capabilities using DENSsolutions In Situ systems

Uppsala University in Sweden expands its TEM capabilities using DENSsolutions In Situ systems

by | Nov 21, 2019 | Chemistry, Partnerships, Wildfire

A DENSsolutions Wildfire double tilt (DT) system with a biasing expansion has been installed at the Uppsala University, Sweden.

Sharath Kumar Manjeshwar Sathyanath and Lars Riekehr checking the new Wildfire holder.

“It will be mainly used by the solid state chemistry group in order to investigate temperature behavior of alloys ”

 

Lars Riekehr – senior research engineer from the Ångström Laboratory in the Department of Engineering Sciences at Uppsala University.

Applications

The Wildfire DT system will be used by the group to research the phase transitions in metals and solar cells.

“After the installation the system was directly tested using solar cell samples. The researchers wanted to see how chemical inhomogeneities in the absorber layer would behave upon heating.”

In particular, Riekehr is pleased with certain features of the Wildfire system, such as the extra lateral shift on heating, the bulging and the stability. Additionally, the Biasing expansion will allow for precise operating voltage control.

He added that he was looking forward to the prospect of being able to offer in situ experiment results to anyone in the department who might need them.

Thank you for reading

To learn more about our Wildfire system:

wildfire product page

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

Queen’s University Belfast joins the group of Climate In Situ users

Queen’s University Belfast joins the group of Climate In Situ users

by | Oct 24, 2019 | Chemistry, Climate, Materials science, Partnerships

Dr. Miryam Arredondo-Arechavala (centre) in front of the (packed) Climate system, together with her PhD student Tamsin O’Reilly (left) and her Postdoc Dr. Kristina Holsgrove (right).

At the beginning of October, DENSsolutions installed a Climate G system at the Queen’s University Belfast, Northern Ireland, UK. 

“We are very excited to have the Climate system in-house. It all began about 3 years ago when I started describing these new amazing holders to my colleagues in the Chemistry department. It took some time but couldn’t be happier! We are really looking forward to trying the different experiments that we have been designing for so long… Now it’s time to get to work and hopefully won’t break too many chips on the way!”
Dr. Miryam Arredondo-Arechavala

Applications

The system will be mainly used by Dr. Miryam Arredondo-Arechavala and her group to study ferroelectrics and other functional materials. Alongside this, it will help accelerate research on ionic liquids performed by the QUILL Research Centre (Queen’s University Belfast’s Ionic Liquid Laboratories) and other catalyst projects at Queen’s University Belfast.

The DENSsolutions Climate holder inserted in the Talos TEM for the first time.

The group running the first test experiment using the Climate software.

Installation and first experiment

The system was installed in less than two days by our Climate product manager Ronald Marx. After this, Marx provided hands-on training for the new group of users. The team was able to start their first In Situ Gas & Heating experiment using their own sample of Zeolite particles which was dropcasted on to the Climate Nano-Reactor. Seeing the first results created a lot of enthusiasm among the group of principal investigators and their colleagues from the chemistry department.

Learn more about our Climate system:

climate product page

Discover publications in which our Climate system was used:

publications

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

Visualizing the dynamic behaviours during carbon nanotube growth in extensive detail

Visualizing the dynamic behaviours during carbon nanotube growth in extensive detail

by | Sep 26, 2019 | Catalyst research, Chemistry, Climate

In situ TEM allows for the direct observation of catalytic processes at relevant pressure and temperature conditions

Original article by Xing Huang, Ramzi Farra, Robert Schlögl and Marc-Georg Willinger

Artist impression showing growth of carbon nanotubes via an iron-catalyzed process. © 2019 DENSsolutions All Rights Reserved

Carbon nanotubes (CNTs) hold many promises, for example in energy storage, high-performance catalysis, photovoltaics, and biomedical devices. Although industrial-scale production of CNTs has been realised, the controllability over the diameter, length, and chirality of CNTs is still unsatisfactory. This is largely due to the lack of atomic information on growth dynamics of CNTs and molecular-level understanding of growth mechanisms. Recently, Huang et al. from FHI Berlin and ETH Zürich have performed an In Situ TEM study on CNT growth and disclosed the growth and termination dynamics of CNTs in atomic detail under relevant conditions. 

The stability of the DENSsolutions Nano-Reactor and the possibility to introduce stimuli, like gas and heating, allowed for the live observation at the atomic-scale:

In Situ TEM video made using the DENSsolutions Climate system, showing Fe-catalyzed multiwalled carbon nanotube growth. Temperature: 800 °C, pressure: 178.65 mbar, diluted H2 + C2H4.

Using In Situ TEM gas and heating, the researchers were able to reveal the influence of pressure and temperature on the growth of CNTs. Previous studies were contradictory about the active state of the catalyst. Now with real-time observations of CNT growth at relevant conditions, researchers were able to reveal not only the active phase of the catalyst but also the rich structural dynamics of the catalyst during the course of CNT growth.

In this study, the Nano-Reactor, the core of the DENSsolutions Climate In Situ TEM system, was used as a carrier for the Fe2O3 sample (precursor material for CNT growth), which was then heated in a diluted hydrogen gas flow as a pre-treatment. The In Situ experiment was started at 150 °C and was followed by a step wise increase up to 800 °C in a gas mixture of H2, C2H4 and He.

To accelerate catalyst research, the DENSsolutions Climate system can be delivered with a dedicated Gas Supply system that enables instant switching between gases and precise control over the gas mixture ratio.

Between 450 °C and 650 °C, the reduction of Fe2O3 to Fe3O4 was accompanied by a collapse of larger particles into smaller ones.

Did you know?

Our Impulse control software comes with a drag & drop profile builder that allows you to design & automate your experiment. It features a wide choice of parameters which enable you to create profiles that suit any sample and application.

WATCH THE VIDEO >

“Thanks to the development of the MEMS-based gas flow Nano-Reactor, we are allowed to perform In Situ experiments inside the chamber of the TEM at relevant conditions. Using the Climate system from DENSsolutions, we have recently carried out a detailed In Situ study on the growth behaviors of CNTs at realistic conditions. On the basis of the real-time observations, we are able to reveal the active structure of the working catalyst and its dynamic re-shaping during the course of CNT growth. Extended observations further reveal three different scenarios for the growth termination of CNTs at the atomic-scale. The presented work provides important insights into understanding the growth and termination mechanisms of CNTs and may serve as an experimental basis for rational design and controlled synthesis of CNTs.”

First and corresponding author – Dr. Xing Huang, ETH Zürich

Learn more about our Climate system and Nano-Reactor:

climate product page

Discover more publications made possible by our Climate system:

publications

Read the original article:

original article

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

Membranes made from Nano-droplets have potential in Medical Research

Membranes made from Nano-droplets have potential in Medical Research

by | Apr 24, 2019 | Chemistry, LPTEM, Ocean

Membranes formed in-lab from nano-droplets could have future use in medicines

For the first time, researchers from the Laboratory of Materials and Interface Chemistry, Eindhoven University of Technology (TUE), with a significant contribution of assistant professor Joe Patterson, have made a comprehensive video of liquid membrane formation using a transmission electron microscope (TEM). They used soap-like nanodroplets submerged in water to create the membrane. Their results are published in Nature, Chemistry and have been highlighted in the Nature, Chemistry News & Views article ‘The molecular Lego movie’.

LPEM Movie of the in-situ self-assembly experiment. Stabilized and cropped. Ianiro, A. et al. Nat. Chem. (2019)

This experiment has continuously recorded the whole process of how the membrane is formed under a microscope. Before this, scientists had to freeze the final membrane and get a snapshot of one or several moments of the membrane forming. This advance is achieved due to a well controlled liquid environment and can be now set in the microscope thanks to the DENSsolutions Ocean system.

Screenshots from the video of the membrane forming on the silicon chip. These were taken using a transmission electron microscope. You can watch the full video here. Ianiro, A. et al. Nat. Chem. (2019)
Membranes are of great interest in research as their selective barriers have potential uses in many fields: drug delivery, water treatment and chemical processes all rely on membrane technology. They are of particular interest in pharmaceutical research as they are the ideal shape to transport a drug through the body and release it only when the membrane finds a specific type of cell, for example, a cancer cell.

The Experiment

The researchers from the Materials and Interface Chemistry group led by Prof. Nico Sommerdijk formed a membrane from soap-like molecules called amphiphilic molecules, which simply means that they interact with both fats and water. Amphiphilic molecules are good building blocks for membranes as they can be lined up with the water-interacting side facing one way and the lipid-interacting parts facing the other way to form larger structures.

The DENSsolutions Ocean In Situ TEM liquid system was essential in this research. The core of the system consists of a dual chip Nano-Cell that sandwiches two chips together to form a microfluidic compartment.

First, the chambers within the tip surrounding the Nano-Cell were flooded with an amphiphilic solvent in order for it to fill the compartment. Then, the solvent was expelled with air, leaving the compartment saturated. Finally, the tip was flooded with water which gradually diffused into the compartment. It was during this stage that the water particles encouraged the solvent particles to organise themselves into a membrane structure.

Step 1. Polymer solvent

Step 2. Air

Step 3. Water

The membrane itself formed in stages. First, the solvent molecules arranged themselves into nanodroplets with a hydrophobic core and a protective hydrophilic shell. The DENSsolutions Nano-Cell created a hotspot of these nanodroplets and they gradually arranged themselves into a hollow membrane.
Diagram of the amphiphilic membrane forming in water. Arash Nikoubashman and Friederike Schmid.

Future Research

Watching how the nanoparticles form and arrange themselves with an electron microscope is a huge step in learning how to manipulate these membranes. The techniques covered in this research will be of interest to scientists working in food science, synthesis chemistry and separation science.

Hanglong Wu, who made a significant contribution to this paper during his PhD period, commented in an interview with DENSsolutions, that the technique “has been extensively used in studying the dynamics and structures of hard materials (for example, metallic nanoparticles) in the aqueous solution in the last decade, but it has been barely employed into soft matter field, mainly due to the inherent high beam sensitivity and low contrast.

“In this Nat. Chem. paper, we actually demonstrate we can probe the soft matter formation with such high contrast. People for sure will start to use the technique in the soft matter field.” – Hanglong Wu

The next stage will be fine-tuning how to manipulate the size and shape of the membrane. This research from Eindhoven is an important step in an exciting field.

If you are interested in the equipment we provided for this research, then contact us to see how we can streamline your experiments.

CONTACT

Membranes formed in-lab from nano-droplets could have future use in medicines

For the first time, researchers from the Laboratory of Materials and Interface Chemistry, Eindhoven University of Technology (TUE), with a significant contribution of assistant professor Joe Patterson, have made a comprehensive video of liquid membrane formation using a transmission electron microscope (TEM). They used soap-like nanodroplets submerged in water to create the membrane. Their results are published in Nature, Chemistry and have been highlighted in the Nature, Chemistry News & Views article ‘The molecular Lego movie’.

LPEM Movie of the in-situ self-assembly experiment. Stabilized and cropped. Ianiro, A. et al. Nat. Chem. (2019)

This experiment has continuously recorded the whole process of how the membrane is formed under a microscope. Before this, scientists had to freeze the final membrane and get a snapshot of one or several moments of the membrane forming. This advance is achieved due to a well controlled liquid environment and can be now set in the microscope thanks to the DENSsolutions Ocean system.

Screenshots from the video of the membrane forming on the silicon chip. These were taken using a transmission electron microscope. You can watch the full video here. Ianiro, A. et al. Nat. Chem. (2019)
Membranes are of great interest in research as their selective barriers have potential uses in many fields: drug delivery, water treatment and chemical processes all rely on membrane technology. They are of particular interest in pharmaceutical research as they are the ideal shape to transport a drug through the body and release it only when the membrane finds a specific type of cell, for example, a cancer cell.

The Experiment

The researchers from the Materials and Interface Chemistry group led by Prof. Nico Sommerdijk formed a membrane from soap-like molecules called amphiphilic molecules, which simply means that they interact with both fats and water. Amphiphilic molecules are good building blocks for membranes as they can be lined up with the water-interacting side facing one way and the lipid-interacting parts facing the other way to form larger structures.

The DENSsolutions Ocean In Situ TEM liquid system was essential in this research. The core of the system consists of a dual chip Nano-Cell that sandwiches two chips together to form a microfluidic compartment.

First, the chambers within the tip surrounding the Nano-Cell were flooded with an amphiphilic solvent in order for it to fill the compartment. The solvent was then expelled with air, leaving the compartment saturated. Then, the solvent was expelled with air, leaving the compartment saturated. Finally, the tip was flooded with water which gradually diffused into the compartment. It was during this stage that the water particles encouraged the solvent particles to organise themselves into a membrane structure.

Step 1. Polymer solvent

Step 2. Air

Step 3. Water

The membrane itself formed in stages. First, the solvent molecules arranged themselves into nanodroplets with a hydrophobic core and a protective hydrophilic shell. The DENSsolutions Nano-Cell created a hotspot of these nanodroplets and they gradually arranged themselves into a hollow membrane.
Diagram of the amphiphilic membrane forming in water. Arash Nikoubashman and Friederike Schmid.

Future Research

Watching how the nanoparticles form and arrange themselves with an electron microscope is a huge step in learning how to manipulate these membranes. The techniques covered in this research will be of interest to scientists working in food science, synthesis chemistry and separation science.

Hanglong Wu, who made a significant contribution to this paper during his PhD period, commented in an interview with DENSsolutions, that the technique “has been extensively used in studying the dynamics and structures of hard materials (for example, metallic nanoparticles) in the aqueous solution in the last decade, but it has been barely employed into soft matter field, mainly due to the inherent high beam sensitivity and low contrast.

“In this Nat. Chem. paper, we actually demonstrate we can probe the soft matter formation with such high contrast. People for sure will start to use the technique in the soft matter field.” – Hanglong Wu

The next stage will be fine-tuning how to manipulate the size and shape of the membrane. This research from Eindhoven is an important step in an exciting field.

If you are interested in the equipment we provided for this research, then contact us to see how we can streamline your experiments.

CONTACT

Experimental determination of the energy difference between competing isomers of deposited, size-selected gold nanoclusters

by | Apr 11, 2018 | Catalyst research, Chemistry, HRSTEM

In situ TEM proves once more its key role in understanding properties of real samples. We show the latest publication using a Wildfire in situ TEM heating system, published on Nature Communications, by the group of Prof. Richard Palmer.

The structure and dynamics of nano-systems are controlled by the multi-dimensional potential energy surface (PES), which describes its free energy as a function of configuration. There have been considerable theoretical efforts to determine the ground-state structures and energy differences between competing isomers of nanosytems in general and of nano clusters in particular. Gold clusters have received much theoretical attention due to the role of structure in the catalytic performance. What is needed now is an experimental handle on key parameters of the PES. Understanding the energy difference between structural isomers is important not only for the design of well-defined materials but also for understanding how these materials will work in situ. For example, if a particular structural isomer is unstable, exposure to high temperatures is likely to drive it towards the ground state (i.e. annealing), altering (for better or worse) the characteristics of the system. Such behavior is likely to be relevant to the applications of nanoparticles, which include catalysis, drug delivery and chemical sensing.

The authors have obtained the energy difference between the most abundant structural isomers of magic number Au561 clusters, the decahedron and face-centred-cubic (fcc) structures, from the equilibrium proportions of the isomers. These are measured by atomic-resolution scanning transmission electron microscopy, with an ultra-stable heating stage, as a function of temperature (125–500 °C). The publication shows clearly the benefits of DENSsolutions heating technology which provides not only ultra high mechanical and thermal stability but also across temperature control across the entire temperature range.

Wildfire in situ heating
Publication
237