Microfluidics for the spectroscopy of carbon nanotubes
We have successfully finalized the process of creating small microfluidic channels on glass chips, having 4 inlet/outlet holes for liquid flow. The fabricated channel structures can be as complex as electron beam lithography can make them. Working channels have the minimum width and depth of 4 µm x 4 µm.
The microfluidics is controlled with Fluigent MFCS, enabling pressures up to 345 mbar. Liquid flow rates range from 40 pl/s up to 1.2 nl/s. Objects in such small channels still run with channel speeds of tens of micrometers or even millimeters per second. With a T-junction structure, droplets of water/oil can be formed and controlled.
The system is coupled with a Raman microscope, enabling at least the detection of carbon nanotubes inside the droplets. However, due to high channel speeds, the droplets need to be stationary to get good measurements. Carbon nanotubes also tend to form bundles and finally block the channels. Raman spectrum of multiple nanotubes was observed.
The stage is now set for further and more complex measurements. Due to its limitations, this system will so far stay only in small-scale research.
...
Olemme onnistuneet viimeistelemään valmistusprosessin, jossa lasilla oleviin mikrofluidistisiin kanaviin saadaan neljä sisään-/ulostuloaukkoa nesteille. Kanavat voivat olla muodoltaan niin monimutkaisia kuin elektronisuihkulitografialla on mahdollista tehdä. Toimivissa kanavissa syvyys ja leveys ovat pienimmillään 4 µm x 4 µm.
Mikrofluidiikkaa hallitaan Fluigent MFCS – laitteistolla, joka mahdollistaa tasaisen paineen aina 345 mbar:iin asti. Nestevirtauksen nopeutta voidaan säätää välillä 40 pl/s – 1,2 nl/s. Objektit hyvin pienissä kanavissa liikkuvat kuitenkin kymmeniä mikrometrejä tai jopa millimetrejä sekunnissa. T-liitoksen avulla voidaan tehdä öljy-vesi pisaroita ja niiden liikettä hallita.
Järjestelmä on yhdistetty Raman-spektroskopiaan, jolloin hiilinanoputket kanavissa voidaan ainakin havaita. Suurten kanavanopeuksien vuoksi mitattavien pisaroiden tulee olla pysähdyksissä mittausten ajan. Hiilinanoputket myös pyrkivät kasaantumaan keskenään ja tukkivat kanavan helposti. Useiden hiilinanoputkien yhtäaikainen Raman-spektri pystyttiin havaitsemaan laitteistolla.
Järjestelmä on nyt valmis uusille ja monimutkaisemmille mittauksille. Rajoitustensa vuoksi järjestelmä pysyy toistaiseksi vain pienen mittakaavan tutkimuskäytössä.
...
![showless](/themes/JYX2//images/showless.png)
![showmore](/themes/JYX2//images/showmore.png)
![showless](/themes/JYX2//images/showless.png)
![showmore](/themes/JYX2//images/showmore.png)
Keywords
Metadata
Show full item recordCollections
- Pro gradu -tutkielmat [29015]
Related items
Showing items with similar title or keywords.
-
Development of microfluidics for sorting of carbon nanotubes
Borovský, Ján (University of Jyväskylä, 2018)Sorting of carbon nanotubes by their chirality is the current bottleneck in the way to their broad employment based on their exceptional electronic and optical properties. Despite the extensive effort, there is no known ... -
Individual arc-discharge synthesized multiwalled carbon nanotubes probed with multiple measurement techniques
Ahlskog, Markus; Hokkanen, Matti J.; Levshov, Dmitry; Svensson, Krister; Volodin, Alexander; van Haesendonck, Chris (American Institute of Physics, 2020)Arc-discharge synthesized multiwalled carbon nanotubes (AD-MWNT), or related MWNTs, exhibit a good quality compared to the more common type of MWNT synthesized by catalytic chemical vapor deposition methods. Yet experimental ... -
Role of Mechanical van der Waals Coupling in the G-Band Splitting of Individual Multiwall Carbon Nanotubes
Avramenko, Marina V.; Hokkanen, Matti J.; Slabodyan, Yuri; Ahlskog, Markus; Levshov, Dmitry I. (American Chemical Society (ACS), 2022)Characterization of multiwalled carbon nanotubes (MWCNT) by Raman spectroscopy is challenging due to their structural complexity, inhomogeneity, and complicated interlayer van der Waals (vdW) interactions. These latter ... -
Spectroscopic studies of semiconducting single-walled carbon nanotubes
Siitonen, Anni (University of Jyväskylä, 2010)The unique nature of optical properties of single-walled carbon nanotubes (SWCNT), together with their promising potential applications, have created enormous interest towards the photophysics of SWCNT. Many aspects ... -
Optical properties of conductive carbon-based nanomaterials
Isoniemi, Tommi (University of Jyväskylä, 2016)The interaction of light with carbon nanomaterials is the main focus of this thesis. I explore several nanostructured systems involving different allotropes of carbon, and characterize them both electrically, if applicable, ...