Most projects at MMK have an application or property as motivation, whereof many have an implication on the environmental goals taken by the Swedish parliament (www.miljomal.se). In the long term there is a wish at the department to increase its research activities in fields related to the environment; e.g. energy, sustainable chemistry, health, which all will have an implication of the vision of a sustainable society. A compilation of present research projects is presented below.

Projects

Modelling biological effects of nanoparticles – Prof. Alexander Lyubartsev

Goal-04.jpgPossible toxic effects of nanoparticles became a matter of concern because of wide use of nanomaterials in everyday life. To get understanding of underlying molecular processes involving interactions of nanoparticles with biological matter computational modelling studies of interaction of biomolecules (proteins, lipids) with inorganic surfaces are carried out. Particular interest is determination of binding energies of aminoacids, polypeptides and lipids to nanomaterials such as titanium oxide, gold, silica, which is further used in predictions of the composition of the nanoparticles protein corona (surface layer of proteins which a nanoparticle becomes covered by after uptake by an organism) and which determines further fate of the nanoparticles in the organism. Funding: EU FP7 program.

Nanostructured materials  based on lignocellulosics for environmental applications: Tailoring of controlled  adsorption and controlled release' – Doc. Aji Mathew

The nanocellulose and nanochtin isolated from natural resources as forest industry residues or side-streams and / or crustacean shells from fisheries being converted to high value products as biobased membranes / adsorbents and nanocapsules will address the to resource efficient processes and product development. Lignin from forest resources which is underutilized today can be converted to functional additives, crosslinkers etc to enhance the membrane/ adsorbant/ nanocapsule processing and performance. Processing of membranes/ adsorbants by vacuum filtration / electrospinning or foaming will lead to multiscaled materials for controlled capture of heavy metal ions, nitrates etc from contaminated water. Like wise, controlled release of fertlizers, pesticides etc through core-shell nanocapsules prepared via electrospraying or electrospinning will contribute to reduced environmental pollution.

Ion transport across nanocellulose-inorganic hybrid membranes – Doc. German Salazar-Alvarez

A large increase in the quantity of heavy metals has been observed in the environment from the expansion of human activities during the last century. In a number of developing countries, various agencies have highlighted the contamination by heavy metals as one of the key five topics of interest due to the widespread associated health problems. This project aims at investigating the transport of heavy metal ions across nanocellulose-inorganic hybrid membranes. Nanocellulose is very attractive for the development of advanced functional hybrid materials based on naturally abundant biopolymers and inorganic nanomaterials. As such, these materials could be potentially exploited as inexpensive components for the fabrication of separation membranes. The work is financed partly by the Wallenberg Wood Science Centre and VR.

Thermally insulating and strong nanocomposite foams by directed assembly – Prof. Lennart Bergström

Thermal insulation plays a major role in controlling the energy efficiency of buildings and there is a need to substantially reduce the thermal conductivity, significantly below the value for air to minimize the required space and materials usage and allow retrofitting older buildings. The purpose of the project is to explore and develop novel, thermally insulating materials based on nanocomposites of renewable and widely abundant raw materials such as cellulose, clay and carbon. The aim is to develop a better understanding on the directed assembly process and the structure-property relations of superinsulating and flame-retardant nanocomposite foams. We want to elucidate how the thermal insulation, flame-reatrdancy and mechanical properties depends on the composition and the structural features of the foams themselves, i.e. the cellular structure and the microstructure of the cell walls.
Funding: Energimyndigheten

Bogolan dyeing- a traditional nanotechnology from Mali – Prof. Lennart Bergström

The main purpose of this project is to investigate the chemistry of the Bogolan dyeing process from Mali. Production of Bogolan cloth continues to be an important part of the local economy and is also exported. Better understanding of the chemistry of the dyeing technique could result in improved processes and a more sustainable use of the resources at hand. Here, the possibility to use local products- e.g. leaves and branches from African birch or n’gallama (Anogeissus leiocarpa), and Balengué clay that is iron rich- and utilisation of the sun for drying is essential to minimise the use of additional energy. In fact, one of the challenges are to counter-act the current development towards the use of (imported) synthetic chemicals and use of energy-intensive processes in dyeing processes.
Funding: VR (Swedish Research Links)

Adsorbents for the separation of carbon dioxide from flue gas mixtures – Prof. Niklas Hedin

The effects of climate change require a reduction of emission of greenhouse gases to the atmosphere and carbon capture and storage is judged to be an important mitigation strategy but its costs are large. Adsorption-driven separation of CO2 could potentially reduce this cost and we have since a few years studied CO2 sorbents in relation to such a process. Routes to synthesize and functionalize CO2 adsorbents with high capacities and selectivities are developed. The links between atomic scale dynamics and macroscopic mass transport and the energy balances are studied in addition to the breakthrough kinetics of CO2 in beds of adsorbents. Funding: Mainly Energimyndigheten but also VR/ ViNNNOVA

Green super capacitors and activated carbons - Prof. Niklas Hedin

Activated carbons (ACs) derived from fossil fuel precursors remain the state of art when it comes to electrode materials in commercial supercapacitors. Both when it comes to sustainability and environmental concerns there is a large demand to use broadly available and natural biomasses to produce ACs. We are studying and developing such green ACs with applications as green supercaps and as adsorbents for water purification. The latter via the removal of organics and arsenate via adsorption on a subphase of Fe3O4
Funding: Berzelii center EXSELENT, Energimyndigheten; collaboration with Biokol AB and ABB.
Patent: Magnetic activated carbon and methods for preparing and regenerating such materials; N. Hedin, et al; PCT/SE2013/050976

Environmentally friendly Iron/Air batteries – Prof. Dag Noréus.

This rechargeable battery chemistry is based sustainable and non toxic metals. It offers high capacities and long cycle life if present stability hurdles can be solved. If we are going to realize an battery electric vehicles as well as large scale grid solutions we have to use easily available, common and non toxic materials such as iron. Höganäs AB is a large producer of iron powder and is involved in this project in an effort to create iron powders suitable for electrochemical applications.
Funding: Energimyndigheten

Environmentally friendly batteries based on Prussian blue analogues. – Prof Gunnar Svensson

Prussian blue analogues can be used as electrode materials in secondary materials. Such electrodes consist abundant and environmental friendly elements and materials. The crystal structures of Prussia analogues blue are very flexible and stable showing excellent cycling performance in batteries. This project concerns detail structural studies of such materials including in situ studies to understand how to further improve them.
Funding: Swedish research council (Röntgen Ångström cluster)

Photochemical water splitting – Prof. Mats Johnsson

Solar energy is highly desirable to use in the quest for generating clean energy. To store the gained energy in a green and sustainable way is another challenge and here compressed hydrogen is an attractive alternative for portable use of larger amounts of energy. In our project we focus on photochemical driven hydrogen production via a photon driven semiconductor coupled with a suitable catalyst, much inspired by photosynthesis in nature. Titania hollow sphere particles decorated with nanoparticles of gold serve well as a catalyst for the oxidation reaction which constitutes the major bottleneck in the overall water splitting reaction. Our work involves optimization and further coupling with a suitable reduction reaction catalyst for increased overall performance.

Transmission electron microscopy study of Pb-free perovskite ferroelectric materials – Dr Cheuk-Wai Tai

Goal-04.jpgThe development of new ferroelectric materials is traditionally driven by the innovations of sensor, actuator transducer and microelectronics. Nowadays, the maintenance of sustainable and environmental-friendly society is also the key motivation. A variety of Pb-based materials are listed in the Restrictions of the Use of Certain Hazardous Substances (RoHS). However, Pb-based ferroelectrics, e.g. lead zironate titanate (PZT), have gained the extension of exemption in every revision. The main problem is that we do not fully understand the structure-property relationship in the Pb-free ferroelectrics. A number of promising Bi-based ferroelectrics are being studied by transmission electron microscopy (TEM). The structure and chemistry of the materials at different length scales are investigated, e.g. the deviation of average crystal structure at atomic level and macroscopic ferroelectric domain morphology. These are very important to help us to understand the correlation to the properties and performance of materials, from both fundamental and technological point of views. 
Funding: Knut and Alice Wallenberg foundation (3DEM-NATUR). 

Porous silicon carbide ceramic filters Prof. Zhijian Shen

Atmospheric fine particulate matters (PM) usually act as the root-cause for the weak visibility of the atmosphere, formation of acid rain and even climate change. The common-occurring type PM2.5 (particulate matter smaller than 2.5 µm) is of special concern due to its detrimental impacts on human health base on the fact that the fine particles can readily penetrate into human lungs. Handling the serious PM2.5 issue is not only urgent but also challenging. The primary sources of PM2.5 originate from coal combustion, vehicle exhausts and industrial discharges. The exhausted smoke dusts from steel/power plants contribute significantly to the generation of PM2.5. In collaboration with SinoSteel, a large Chinese company, we are attempting to design ceramic filters with hierarchical heterogeneities that can purify the dusts from steel/power plants.
Funding: Vinnova/VR through EXSELENT center on porous materials.

Design, Functionalization and Characterization of Nanoporous Materials – Xiaodong Zou

Porous materials have numerous applications from very advanced ones as complex heterogeneous catalysis to simpler ones adsorbents of metals or as softener in washing powders. Efficient catalysts can replace processes with a negative impact on the environment and efficient and cheap adsorbents can remove poisonous metals and other substance. This project study such materials, their synthesis and characterisation. Funding: VR/Vinnova

Conservation Strategies of Archaeological Wood – Magnus Sandström

Goal-04.jpgX-ray spectroscopy allows characterization of many types of sulfur compounds accumulated in the wood of historical shipwrecks on the seabed. The amount and speciation of the sulfur compounds, which originate from hydrogen sulfide produced by sulfate-reducing bacteria in anaerobic conditions, are analyzed by sulfur K-edge XANES (X-ray Absorption Near Edge Structure) and scanning x-ray fluorescence (XRF) of wood cores from shipwrecks displayed in museums worldwide. Iron sulfides are often present in wooden artefacts affected by acidity, while organically bound sulfur (mainly thiols, disulfides) accumulates in lignin-rich parts of the cell walls. The results are used to evaluate and adapt conservation treatments. Funding: The Swedish National Heritage Board (Y. Fors) and SU (Faculty of Sciences)