Active Nanocomposite Materials

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1 Active Nanocomposite Materials Contact: Prof. Jorma Jokiniemi The aim of this project was to develop tailored functional nanocomposite materials for industrial applications. The produced materials find multitude applications ranging from gas and biomaterial filtration to printed electronics, sensors and antennas as well as production of OLED displays. However in this project, the main focus was on development of Si based materials and Si-metal composites for the anodes of Li-ion cells. The project tried to solve the issues related to the current anode technology of Li-ion cells that hinder the development for long life industrial battery application such as HEV or standby (for sustainable energy device). One of the most important objectives of the project was to develop industrially viable techniques to synthesise these materials. The production techniques applied were novel gas phase methods providing low energy and raw material usage as well as high purity and yield. Three different techniques induction nucleation, chemical vapour synthesis and spray drying were utilised and compared. The nanocomposite materials produced and characterized during the project included: Micro- and nano-sized silicon particles, silicon monoxide, composites (e.g. Si-Cu, Si-Fe) and coated and/or functionalized Si (e.g. Si/PAA, Si/POSS, Si/metals) for Li-ion battery applications. Preceramic and nanoceramic materials (e.g. Si/C/H, SiC) with high durability, thermal stability and conductivity. Metal composite materials (e.g. Ag, Cu, Cu/SiO 2 ).

2 Generation and stimulation of Liquid Flame Spray (LFS) coating Mikko Tuominen Titanium dioxide (TiO 2 ) and silicon dioxide (SiO 2 ) nanocoatings were successfully deposited on-line at atmospheric conditions on paper, paperboard and low density polyethylene (LDPE) laminates using a thermal liquid flame spray (LFS) method. LFS-coatings possess high surface roughness, in micro- and nano-scale, and hence the superhydrophilic (<10 ) or superhydrophobic (>160 ) surfaces can be created. The superhydrophobic surfaces can show a high adhesion to water droplets or low adhesion to water droplets, depending on the substrate and LFS parameters used. Figure 1. The stimulation methods of LFS-TiO 2 coated paperboard surface. TiO 2 is a photoactive material, therefore the wettability of the TiO 2 coating can be adjusted to any precise level from superhydrophilic to superhydrophobic. UV light, corona or atmospheric plasma treatment can be used to decrease the CAW from >160 down to <10. The hydrophobicity of the TiO 2 surface can be returned by heat treatment or plasma deposition. Furthermore, the conversion of TiO 2 coating wettability can be done repeatedly.

3 Life Cycle Assessment Framework and Tools for Finnish Companies (FINLCA) Jyri Seppälä, Riina Antikainen Life cycle assessment (LCA) and related methods (MFA, SFA, EE-IO, carbon footprint, water footprint, ecological footprint, thermodynamical methods) are commonly used in assessing environmental impacts of products and services. The field is under continuous international development. The project identifies problems and obstacles in the use of life cycle methods, especially from the corporate perspective, and develops knowledge and know-how on LCA and related methods. A network of research institutes and companies was established to create a national roadmap on how life cycle methods can be promoted in Finnish industries. The project aims at developing life cycle approaches and a framework to guide, which are the most feasible methods and best practices. The aim is also to improve the environmental competiveness of the Finnish companies. The research project constitutes of a theoretical part and several case studies. Theoretical part focuses in the recent development in life cycle methods. Case studies and information from companies is utilized to support the theoretical findings. The focus of our study is on Finnish companies, but the results can be widely applied when use of life cycle approaches is promoting to support decision making on environmental sustainability

4 Printable biosensor surface BioFace Contact: Vesa Abstract: We have developed methods for biofunctionalization of plastics by printing methods. Chimeric avidin was used to build a generic biotin-binding surface, which can be used for tailoring of a broad range of different biosensing surfaces. Chimeric avidin was found stable over 3-month storage period in a printed form. In addition to bioink allowing direct deposition of chimeric avidin in functional form, we have also developed ink allowing preparation of porous material by printing. The developed protocols are valuable in applications, where versatile and cost-effective manufacturing methods are needed

5 Novel methods to formulate polymer nanocomposites and tailor their dielectric behavior (NANOCOM) Ass. prof. Kari Kannus (Tampere University of Technology) ABSTRACT: The main targets of the three-year research project NANOCOM was to innovate, create and characterize novel electrically insulating polymer nanocomposites where the electrical, mechanical and thermal properties are highly tailored to achieve more cost-effective, energy-effective and hence environmentally better materials for the electrical and electronics insulation technology. Additionally, one major target was to explain the measured materials properties using molecular modelling and electronic structure calculation methods. The best results were achieved with 5 wt-% silicapolypropylene nanocomposite: the AC and DC breakdown strength were increased by 20 % and 50 %, respectively. This achievement gives a very promising possibilities to develop and test AC and DC power capacitors with high energy density for electric transmission and distribution networks, in energy storage systems (for wind and solar power plants) and for power devices (e.g. in hybrid and electric vehicles). For example, if we can increase the continuous voltage used in a DC capacitor by 30 %, we will get almost 70 % more power out of the capacitor, which in turn means that we will need only approx. 60 % of the amount of capacitors for some application. Consequently, we can save a lot of space and also various raw materials and, hence, also the energy consumption and waste burden will be lower

6 Chemical looping combustion for carbon capture Dr. Pertti Kauranen, VTT, Abstract: Carbon capture and storage (CCS) can be used to capture CO 2 from fossil power plants in order to limit CO 2 emission to the atmosphere. One of the most efficient prospective CCS technologies is chemical looping oxyfuel combustion (CLC) process in which oxygen is filtered from atmosphere using a redox metal powder circulated between two interconnected fluidized bed reactors. CLC process has been modelled at particle, reactor and power plant scales. Alumina supported nickel and iron oxides have been synthesized by spray drying and characterized by SEM and TG as well as bench scale CLC reactors. The models have been verified using experimental data. International networks and building of domestic research infrastructure has been initiated

7 ALEBOND Riikka Puurunen ALD Abstract: In ALEBOND, technologies have been developed for controlling the stiction of two parallel, smooth surfaces in silicon and other wafer handling as well as in the fabrication of MEMS devices (MicroElectroMechanical Systems). Coatings just a few nanometers thick, made by the ALD (Atomic Layer Deposition) technique, are used, and the surface adhesion properties are engineered by controlling the ALD coating type and especially its roughness. Smooth nanolayers allow the permanent attachment of two smooth wafers to each other. After high-temperature annealing, wafers with a buried oxide such as alumina can be made, to be used as tailored starting substrate in MEMS fabrication. Rough nanolayers, in turn, can be used to avoid surface attachment (stiction) in MEMS devices with moving parts. The developed technologies are fully up-scalable to industrial production

8 Novel steel-rubber-composite hybrids Dr. Minnamari Vippola Tampere University of Technology, Department of Materials Science Motivation for the K3MAT project (Light and wear resistant hybrid materials) can be described with the following statement: To enable the utilization of the best material properties of different material grades, hybrid structures are developed. Hybrid materials have unique properties, which cannot be achieved when using the respective materials individually. In this study as a part of the K3MAT project, the aim was to develop a light weight, wear resistant hybrid structure which has improved damping and impact properties to be used e.g. in machinery. In addition, a low cost manufacturing method was one of the targets. Studies were made for layered hybrid structure consisting of cold rolled steel, EPDM based rubber and glass fiber reinforced epoxy (FRP). The structure is manufactured by vulcanizing the rubber between the steel and the composite layers under heat and pressure without additional coupling agents. Adhesion and impact properties of the structure were investigated by mechanical tests and microscopy was used for microstructural characterization of the hybrid. Adhesion tests revealed that the adhesion at the steel-rubber interface is better than at the FRPrubber interface. However, the adhesion level at both interfaces is comparable with those measured from non-pretreated steel based fiber metal laminate. In addition, adhesion was enhanced with decreasing rubber thickness. Preliminary impact tests showed the positive effect of increasing rubber thickness. According to the study, it was evident that a steel-rubber-frp hybrid structure can be manufactured by a simple and fast method leading to good adhesion properties. However, the impact and damping properties of the structure needs to be investigated further to establish the improved properties of the hybrid structure comprehensively. DM

9 Modeling of wear resistance of composite thermal sprayed coatings (MOTRICOT) Anssi Laukkanen Advanced thermal spray coating processing methods offer the means to tailor surface structure, properties and performance. Numerical modeling techniques have been developed within MOTRICOT to carry out optimization of the process-structure-properties-performance (PPSP) chain. Such modeling accounts for local material microstructural features, such as strengthening particle geometry and distribution within a binding material. Analyses were performed both for synthetic and genuine structures, the genuine models generated directly on the basis of SEM image recognition. Simple synthetic models Synthetic models Simplistic trends Mesoscopic synthetic models Complex trends and distributions Genuine models Failing and wearing material Actual microstructure