Aerosol technology offers new opportunities for manufacturing materials and adapts to the principles of green chemistry.
New materials produced with aerosol technology help achieve sustainable development and a carbon-neutral society
"The idea behind sustainable development and the circular economy is that nothing valuable is thrown away. Instead, the used materials or side streams can be reintroduced to create new products contributing to carbon-neutral solutions," says Anna Lähde, Professor of Aerosol Technology at the Department of Environmental and Biological Sciences.
“This saves natural resources and reduces the environmental load while maintaining our standard of living in a more sustainable way.”
Professor Lähde’s research field, aerosol technology, is in many ways linked to sustainable development. Aerosol synthesis processes are very efficient and minimise, e.g., the amount solvents needed to produce finely tuned materials. In addition, sustainable precursors such as biomass, industrial side-streams, etc., are utilised as precursors and the produced materials are applied in energy storage, carbon capture and wastewater purification. This further supports the goals related to the circular economy and carbon neutral society.
“After graduating, I ended up working with aerosols, and since then I have been studying aerosols, i.e., liquid or solid particles that are suspended in gas, such as air. My current research focus is on how aerosols and aerosol technology can be utilised in material synthesis and how the properties of materials can be optimised for different applications,” she explains.
“There are several different uses for the materials we study, but our group focuses especially on energy storage, i.e., materials used in Li-ion batteries and next-generation batteries. We are also studying high surface area and nanostructured materials and catalysts that can be used, for example, in carbon capture and water purification.
Lähde defended her doctorate in chemistry at the University of Jyväskylä and has worked for several years at VTT, among other employers. She came to the University of Kuopio in 2008 as a postdoctoral researcher in a project examining the use of silicon in lithium-ion batteries.
“Since then, I have been working at the University of Eastern Finland and studied similar subjects. In 2017, I received five-year funding from the Academy of Finland Research Fellowwhich was granted particularly for the development of bio-based carbon structures.”
While Lähde's research group conducts basic research, its applications are carefully considered. Business cooperation is important - one must really think about what industry and companies need.
“At the moment, our group's research has focused on materials produced using the principles of green chemistry and sustainable development and their applications in general.”
Improved battery life and more efficient recycling
More efficient solutions should be found, for example, for energy storage. New battery materials are currently very interesting.
According to Lähde, transport - especially electric cars - should be developed in a sustainable way without depleting natural resources at the other end of the production chain.
If we all had electric cars that operated with the current battery solutions, the natural resources would be insufficient.
Anna Lähde
Professor
"To this end, alternative materials solutions are needed that can replace the materials currently used in batteries. An example of this is the use of wood biomass as a substitute for synthetic graphite.
Of course, we also need efficient recycling of materials," she says.
Lähde’s research group will continue to advance this research in the BATCircle2 project funded by Business Finland. The group will also develop new solutions, so-called next-generation lithium-sulphur batteries, which will provide more efficient ways of storing energy in the future. However, there are still challenges in lithium-sulphur batteries and they are not widely used commercially, so there is much room for development.
“After all, the advantage of lithium-sulphur batteries is their high energy density compared to current batteries. With the help of materials science, we aim to create structures that can solve the current challenges and extend their cycle life by adapting the increase in volume and preventing sulphur from escaping from the structures during battery charge-discharge cycles.,” says Lähde.
Another side of the issue of sustainable materials also includes the recycling of Li-ion batteries and how all valuable materials from the batteries can be recovered. When recycling batteries, materials must be separated and purified so that they can be reused in batteries. This is a challenging task.
“There are processes that allow nickel, cobalt and manganese to be recovered at the moment, but carbon or more specifically graphite should also be recovered. However, the graphite used in Li-ion batteries must be extremely pure more than 99.95%, which poses challenges for the reuse of graphite from used batteries. Our group is developing a thermal method to achieve these purity requirements.”
“Regarding battery materials, research is progressing very fast. We currently have two on-going projects that focus specifically on anode materials. We are studying how aerosols and high temperature processes can be utilised and how the materials used in batteries can be separated, purified and reused,” says Lähde.
“The results are promising and will hopefully enable us to improve the adequacy of raw materials throughout Europe. In addition, this will naturally affect the competitiveness of Finland and also of Europe.”
Green chemistry means new solutions for carbon capture
In addition to new energy solutions, methods such as carbon capture are needed which can contribute to reducing the amount of greenhouse gases in the atmosphere and thus technically enable our current lifestyles.
The aerosol processes developed in Lähde’s research group are simple, one-stage methods that can easily produce nanoparticles without large amounts of solvents, which reduces the chemical loads generated in the production.
“The produced nanomaterials and composites, such as titanium dioxide, can function as photocatalysts, among other things. They enable many reactions through sunlight, which in turn can reduce the carbon footprint,” says Lähde.
The next steps in research are new, more efficient materials that can capture carbon dioxide. It is hoped that by reducing its amount, it will also be possible to control global warming.
ANNA LÄHDE
Professor, aerosol technology, from 1 September 2023 until further notice
Assistant Professor, University of Eastern Finland, 2019–2023
Academy of Finland Research Fellow 2017–2022
Docent (Fine Particle and Aerosol Chemistry), University of Eastern Finland, 2014
Doctor of Philosophy (Chemistry), University of Jyväskylä, 2000–2008
Positions held:
Research and development of sustainable materials and research infrastructure.
Teaching related to the topic, student guidance and leading a research group.
Comprehensive and close cooperation with both Finnish and foreign research organisations and companies.
