MMD research focuses
Our current research focuses involve:
- Breath figures & hierarchical self-assembled structures
- Functional bioaerogels & biocryogels
- Photo-controllable surfaces
- Nanocellulose in energy devices
- Replication of the nature’s functional surfaces
- Plant virus particles as nanomaterials
- Polymer actuators
- Wearable pressure/strain and temperature sensors
- Solar cells
Breath figures & hierarchical self-assembled structures
We develop novel methods for nano- and microstructure deposition and investigate their use in bio/mechano-sensing with a potential application in wearable devices. This object can be achieved via incorporating different self-assembly processes in one synthesis procedure, for example, combining breath figure techniques, block copolymer phase separation and nanoparticles self-organization. In addition, the use of dip-coating, which is a cost-effective, simple and scalable technique for film deposition, can reveal a nanostructured pattern without post-processing.
Functional bioaerogels & biocryogels
Our group aims to understand, how bio-based materials – even biowaste – can be converted into functional highly porous materials, called aerogels and cryogels. In our current work, biodegradable materials are used to prepare the aerogels, which could achieve the promising material properties, such as high specific surface area, low density and high porosity. According to the different requirements of final applications, the material properties can be easily tuned by versatile supramolecular crosslinking strategies.
We combine photo-responsive azobenzene with matrix polymer by supramolecular interaction and then coat the complexes on thick stretchable substrate to build a double-layered structure. Upon stretching, the wrinkle structure will be created due to the mechanical properties mismatch between the top layer and substrate. Under the light illumination, wrinkle structure will be erased and the rate of erasure is tunable by adjusting the azobenzene content. Furthermore, with wrinkle structure, the surface area will be significantly increased, which could be used for further deposition and potential applications.
Nanocellulose in energy devices
Is it possible to produce/store energy from trees or other bio-based materials only? Our main focus is to fabricate “green & sustainable” materials that are based on cellulose, the most abundant organic compound on earth, to reduce the environmental pollution and CO2 emissions in the world.
Cellulose can be employed in flexible/stretchable energy storage devices, including batteries and supercapacitors, as an active material or/and electrolyte, due to its low cost, high biocompatibility, and biodegradability. It can also be used as transparent and flexible films in solar energy applications (e.g. solar cells) and replace glass, for easier recyclability and greener planet.
Replication of nature’s functional surfaces
Fascinating properties in nature have always inspired scientists to mimic and employ their functionalities. Among them, some plant leaves, such as those of many cabbage plants, benefit from the possibility of removing dirt as the rain falls and the droplets sweep the surface clean. Such surfaces are known to be self-cleaning. The self-cleaning property is quite desirable in various industries. For example, they can be quite useful in solar cells where their efficiency degrades as dirt piles-up. Here, we pursue replication of such functionalities by imprinting the surface structures of promising leaves.
Plant virus particles as nanomaterials
Plant viruses are emerging nanomaterials with highly-customizable and complex features. Potato virus A (PVA) is a plant virus, which produces long flexuous nanowire-like particles with very high aspect ratio. Their ease of production, monodisperse nature and customizability makes them highly suitable candidate for nanomaterial applications. In our group, we explore novel strategies to implement PVA-nanoparticles in emerging photovoltaics.
Certain polymer materials, such as nylon, inherently possess thermally activated structures. In our research we make yarns from twisting and coiling this type of a material to produce thermally-triggered actuators. These actuators either contract or expand based on the provided thermal energy, and they could be used in applications such as smart fabrics, wearable technology, and soft robotics. Our aim is to understand the polymer structure and the formation of the yarn itself to improve the functioning of our mobile material, and in addition scope out future design possibilities for such a material.
Wearable pressure/strain and temperature sensors
Our group is devoted to the fabrication of novel pressure, strain and temperature sensors based on nanomaterials. Our research includes fundamental materials and chemistry innovations, as well as important device applications for monitoring human health. We create and apply innovative sensors to understand complex human electrophysiological activity.
The solar cell technology is the most promising green technology when compared to other sources of energy, owing to the availability of the Sun’s energy across the planet. Unfortunately, the instability of photovoltaic modules that are exposed to heat, moisture, as well as ultraviolet (UV) and infrared (IR) irradiation hinders their commercialization. In MMD group, our aim is to improve the longevity of solar modules using designed functional materials either inside a solar cell's architecture or through the applied coatings. Furthermore, advanced functional soft materials can bring several modifications to solar cells, for example, flexible and lightweight substrates.
The research project "Improving longevity of solar cells through integration of added functions", funded by Fortum, has been recently launched in our research group.
Multifunctional Materials Design
Group led by Professor Jaana Vapaavuori
Multifunctional Materials Design: research group members