Print Page | Contact Us | Report Abuse | Sign In | Register
Graphene Updates
Blog Home All Blogs

Graphene infrared radiation shielding

Posted By Graphene Council, The Graphene Council, Monday, July 22, 2019
Updated: Thursday, July 18, 2019

Scientists of the Warsaw University of Technology Faculty of Chemistry and Process Engineering use graphene oxide and graphene-related compounds to develop new materials for infrared radiation protection. Their IR-GRAPH Project was funded by the National Centre for Research and Development (NCBR).

“We want our materials to act as a barrier to both heath absorption and release,” says Marta Mazurkiewicz-Pawlicka, Ph.D. Eng., who supervised the work. “They are composites. We create them of polymers, using two types at this time. We use graphene materials with added metal oxides, such as titanium oxide, as the filler.”

Such a combination provides efficient screening. “Graphene materials are added to absorb radiation while metal oxides are supposed to disperse it,” explains the researcher.

Competitive Material

The market already offers, for example, window films for radiation protection. However, the materials developed by the scientists of the Warsaw University of Technology can compete with them. “They contain about 5% of added filler to reduce the temperature by a few degrees Celsius,” says Doctor Mazurkiewicz-Pawlicka. “We obtain similar results by adding 0.1%, that is 50 times less, of the filler.”

But for now, the team is focused on the materials alone rather than on specific applications. And potential applications are quite easy to see, just to mention windows as well as façades or even fabrics. The materials would protect against heat losses in winter and they would prevent overheating in summer.

For buildings or vehicles, that could mean an alternative to the now common air-conditioning systems, which as we know are extremely energy-intensive. The greater the desired modification of the ambient temperature in a room, the more energy is needed to achieve it. A less energy-intensive support would bring savings in the budget and benefits to the environment.

Looking into the future

Warsaw University of Technology scientists have carried out short-term tests. The results are promising but still a number of aspects must be investigated further, e.g. the polymer performance under UV radiation or at elevated temperatures or at a modified humidity. It is important to test the existing solutions both under various conditions and over a long time. Such testing could be done in a climatic chamber where a material sample could be placed and monitored.

“For instance, we have to work on the color to be able to use our materials in window films as the current color, which is in shades of grey, obscures visibility,” says Doctor Mazurkiewicz-Pawlicka. “We want to find new polymers that could be used as warp in our materials.”

A Collaborative Act

The team led by Doctor Mazurkiewicz-Pawlicka included Leszek Stobiński, Ph.D., D.Sc., Artur Małolepszy, Ph.D. and a group of students working on their engineer’s or master’s theses under the project. Members of the Chemical and Process Engineering Student Research Group also made a contribution. “They have built a device to measure how efficient our films are,” says Doctor Mazurkiewicz-Pawlicka. “It comprises an infrared lamp and a sensor which measures the degrees of temperature reduction.”

The WUT scientists closely collaborated with Tatung University, Taiwan, under the IR-GRAPH project. They also received support of the University of Warsaw Faculty of Physics. “Faculty Dean Prof. Dariusz Wasik and Andrzej Witowski, Ph.D., D.Sc., are experts in solid-state physics and they have carried out spectrometer measurements for us”, says Doctor Mazurkiewicz-Pawlicka.

Why IR screening?

Graphene is mainly associated with electronics and automation applications. Graphene use for radiation screening has not been that common yet. “There are references reporting that graphene can offer screening against electromagnetic radiation,” says Doctor Mazurkiewicz-Pawlicka. “This aspect is widely researched in the context of microwave radiation and, recently, also terahertz radiation, primarily for military applications. We thought we could investigate graphene properties for infrared radiation as this is quite an unexplored territory.

Infrared radiation has the wavelength ranging from 780 nanometers to 1 millimeter. It combines with the visible light and UV radiation to create the spectrum of sunlight. Excessive sunlight has a harmful effect on human skin. As much as 50% of sunlight which reaches the Earth’s surface is infrared radiation (which can be felt as heat). That is why IR screening is vital.

Tags:  Andrzej Witowski  Artur Małolepszy  Dariusz Wasik  Graphene  Leszek Stobiński  Marta Mazurkiewicz-Pawlicka  National Centre for Research and Development  polymers  Warsaw University of Technology 

Share |
PermalinkComments (0)
 

How is graphene holding up at Warsaw University of Technology?

Posted By Graphene Council, The Graphene Council, Tuesday, March 26, 2019
Updated: Tuesday, March 26, 2019

Warsaw University of Technology (“WUT”), for more than 10 years, has been involved in extensive research into graphene, its applications and production techniques, in both domestic and international projects (it boasts more than 250 scientific publications in international journals and several patents). As the only institution of higher education in Poland, it is a member of the Graphene Flagship programme, the EU’s biggest ever research initiative. The project work is carried out among others in the cutting-edge Center for Advanced Materials and Technologies (CEZAMAT) and is scheduled to continue until at least March 2022.

The University cooperates with scientific and industrial partners from Sweden, the United Kingdom, Austria and China to further advance the technology of epitaxial graphene on silicon carbide for applications such as 5G technologies. WUT’s PhD students engage in joint research at scientific institutions across Europe, including Cambridge and Madrid.

WUT pursues a number of high-end national projects that focus on research into graphene and new two-dimensional materials: Team-Tech (Foundation for Polish Science), Lider and TechmatStrateg (National Centre for Research and Development), Sonata and Preludium (National Science Centre), Diamentowy Grant (Ministry of Science and Higher Education).

The University has established the Graphene Laboratory (Faculty of Chemistry and Process Engineering) dedicated to the carbon nanomaterial production, characterization and exploration of new applications, e.g. hybrid fluorescent materials or infrared radiation absorbers or even some unusual solutions such as the development of new polyester gelcoats to be used in the construction of new generation yachts, Delphia Nano Solution. It is also a promoter of spin-offs aimed at the transfer of graphene technologies and applications to industry and putting them to use for commercial production. Moreover, numerous businesses collaborate with Warsaw University of Technology in application research under joint projects and bilateral agreements.

The work on graphene at Warsaw University of Technology covers two types of this material: graphene flakes and epitaxial graphene (film). “The University has several processing lines producing graphene flakes with the use of both chemical methods of oxidation and reduction of graphene oxide and the so-called liquid-phase direct exfoliation method. Last year, a new method was launched for the production of graphene flakes which is cheap, green and easily scalable for industry. WUT is now in the process of patenting this new technology,” says Prof. Mariusz Zdrojek, head of the graphene research group at  WUT’s Faculty of Physics.

The University has also launched an epitaxial graphene growth (on copper foil) for the purpose of its own application research. Moreover, it has developed and launched the growth technique of new two-dimensional materials in the graphene family, MXenes. The synthesis of other two-dimensional materials, i.e. molybdenum disulfide (MoS2), using the epitaxial growth method has also been elaborated.

Some of the more exciting graphene applications developed by the Warsaw University of Technology in collaboration with the Polish industry include:

- New generation ultrafast infrared photodetector created in 2015 under the Graf-Tech project. The device, in which graphene plays a key role, is in the pre-implementation phase (Faculty of Physics);

- Electronic nanodevices to be used in high-frequency electronics (for fast detectors, sensors or diodes), a product of the Lider project. Currently, work is underway on the patent application (Faculty of Physics);

- New nanocomposites for electromagnetic radiation protection for cybersecurity, electronics, aerospace and 5G technology. The patent application is pending with the European Patent Office (Faculty of Physics);

- Graphene thermal pastes for electronics as novel materials for heat transfer. Conductive graphene inks and pastes suitable for multi-surface printing technologies (e.g. clothes or banknote printing), where they act as transparent electrodes. Patented technology (Faculty of Mechatronics);

- Membrane technologies for mobile drinking water treatment plants, where use of graphene has improved selectivity. (Faculty of - Material Science and Engineering; Faculty of Chemical and Process Engineering);

- Graphene as an anti-corrosion coating, a product of the GrafTech project as part of the joint effort with a research partner (Faculty of Physics);

- other, i.e. flexible displays, pressure sensors, glucose sensors or amino acid biosensors.

For the past few years WUT’s researchers have been also conducting research into the application of other 2D materials. This  has resulted in creation of the materials’ potential new applications eg in the production of composites for the space and aerospace industries or as an innovative platform for drug delivery, new optoelectronic nanodevices or devices for terahertz electronics applications.

With the appropriate know-how, materials and infrastructure and access to the country’s best specialists,  Warsaw University of Technology remains at the leading edge of the development of technologies and applications for other two-dimensional materials, considered to be of strategic importance to advanced industry sectors.

Tags:  2D materials  Graphene  Graphene Flagship  Mariusz Zdrojek  Warsaw University of Technology 

Share |
PermalinkComments (0)