How does a Langmuir trough work?
How does a Langmuir trough work?
A Langmuir–Blodgett trough (LB trough) is a laboratory apparatus that is used to compress monolayers of molecules on the surface of a given subphase (usually water) and measures surface phenomena due to this compression. It can also be used to deposit single or multiple monolayers on a solid substrate.
What does Langmuir-Blodgett film do?
The Langmuir Film Balance The surface area of the trough can be varied by sweeping movable barriers over the surface of the trough. The barriers are made of Delrin, a hydrophilic material, and heavy enough to prevent any leakage of the monolayer beneath the barrier.
What are Langmuir monolayers?
Langmuir monolayers are single monomolecular layers of a given surface active molecule at the air/liquid interface. The Langmuir monolayer can be compressed to given values of area per molecule. The changes in the surface tension of the air/liquid interface are monitored by a Wilhelmy plate microbalance.
What is the Langmuir-Blodgett technique?
The Langmuir-Blodgett (LB) technique is a way of making supra-molecular assembly in ultrathin films with a controlled layered structure and crystal parameter, which have many envisioned technological applications for optical and molecular electronic devices as well as signal processing and transformation.
What are the advantages of LB films?
LB films can be used as passive layers in MIS (metal-insulator-semiconductor) which have more open structure than silicon oxide, and they allow gases to penetrate to the interface more effectively. LB films also can be used as biological membranes.
How are self assembled monolayers formed?
Figure 1 Self-assembled monolayers are formed by simply immersing a substrate into a solution of the surface-active material. The driving force for the spontaneous formation of the 2D assembly includes chemical bond formation of molecules with the surface and intermolecular interactions.
What are self-assembled monolayers used for?
SAMs have been used for studies and applications in many areas. A few examples include surface wetting, non-fouling property, electrochemistry, surface passivation, protein binding, DNA assembly, corrosion resistance, biological arrays, cell interactions, and molecular electronics.
What is the meaning of self-assembled?
Self-assembly is the process in which a system’s components—be it molecules, polymers, colloids, or macroscopic particles—organize into ordered and/or functional structures or patterns as a consequence of specific, local interactions among the components themselves, without external direction.
What does a monolayer look like?
In cell culture a monolayer refers to a layer of cells in which no cell is growing on top of another, but all are growing side by side and often touching each other on the same growth surface.
How are self-assembled monolayers formed?
How did the Langmuir Blodgett film get its name?
Langmuir–Blodgett films are named after Irving Langmuir and Katharine B. Blodgett, who invented this technique while working in Research and Development for General Electric Co. Advances to the discovery of LB and LM films began with Benjamin Franklin in 1773 when he dropped about a teaspoon of oil onto a pond.
How are Langmuir Blodgett films built up layer by layer?
Langmuir–Blodgett films are inherently 2D-structures and can be built up layer by layer, by dipping hydrophobic or hydrophilic substrates into a liquid sub-phase. Recently, it has been demonstrated that Langmuir–Blodgett is an effective technique even to produce ultra-thin films of emerging two-dimensional layered materials on a large scale.
What did Langmuir and Blodgett discover about organic moieties?
While working for GE, Langmuir and Blodgett discovered that when a solid surface is inserted into an aqueous solution containing organic moieties, the organic molecules will deposit a monolayer homogeneously over the surface. This is the Langmuir–Blodgett film deposition process.
How are Langmuir films used in nanoscience?
These include thermal evaporation, sputtering, electrodeposition, molecular beam epitaxy, adsorption from solution, Langmuir-Blodgett technique, and self-assembly. The Langmuir- Blodgett (LB) technique is one of the most promising methods for the preparation of thin films as it enables