Magnetics and Materials Research Group
Research into the production, characterisation and application of magnetic materials.
Our research focuses on synthesis, characterisation and modelling of quantum materials, functional composites and advanced material structures with particular interests in magnetic, sensing, energy harvesting and biomedical applications.
The core research areas include:
- Magnetic properties and application of electrical steels
- Magnetic sensors and systems for medical applications
- Deformation and fatigue in biomaterials and nanocomposites
- Graphene based functional ceramic materials and composites
- Thermoelectric materials and devices for energy harvesting
- Solution processed solar cells and concentrated hybrid systems
- Semiconductor nano-optics and quantum photonics
The Thermoelectric and Photovoltaic Laboratory
This research activity relates to thermoelectric materials and devices such as energy harvesting from waste heat recovery from automotive exhaust processes and Peltier cooling for various applications, including water desalination systems. In 2012 new research lines based on various photovoltaic technologies and thermomagnetic generators and their application with thermoelectric modules were established. Further research includes the deposition of functional thin-film materials by Pulsed Laser Deposition (PLD) and screen printing for application in dye-sensitised solar cells (DSC). This research relates to the preparation, characterisation and optimisation of semiconducting oxide thin films. The PLD system is an advanced facility which enables the preparation of a wide range of thin films in a highly controlled manner. The deposited materials range from multicomponent semiconductors, via alloys, to pure metals. The apparatus can be used for R&D, pilot production, and full production capabilities for a variety of applications depending on demand and productivity.
Further research includes the computer simulation of thermoelectrics (TE) including finite element modelling of TE modules. This work is conducted in parallel with experimental data acquisition to develop a rigorous understanding of the transport properties of semiconductors, device physics, fabrication and characterisation. The AC response of TE elements for impedance spectroscopy has also been calculated which can provide rapid measurement of material properties.
Energy and power magnetics
Research in the Wolfson Centre for Magnetics focuses on several areas related to the production, characterisation and application of magnetic materials.
The Centre has an established international track record in research on aspects of soft magnetic materials and research and consultancy projects are carried out for organisations ranging from world leading multinationals to local small companies.
Energy losses associated with power magnetic systems account for as much as 10% of electricity generated in the UK, and just a 3% saving on magnetic losses is equivalent to 3-4 million tonnes of carbon dioxide emissions per annum.
The group participates in the following projects:
The FP7 GLOBASOL project which aims to integrate thermoelectrics with solar cells, splitting the incoming radiation by wavelength, so that short wavelengths are converted by the solar cell and long wavelengths by the TE generator. The fabrication and characterisation of nanostructured and bulk thermoelectric material (Bi2Te3) are also being investigated for room temperature operation. The Globasol project has partners in UNIPMN (Italy) who are leading the project, the Fraunhofer Institute (Germany), TUD (Germany), EPFL (France), UAM (Spain) and EXEGER (Sweden).
The EPSRC Supergen SUNTRAP project with primary objectives to reduce costs and increase the performance and lifetime of photovoltaic renewable energy generation systems. This is designed by utilising optical concentration and integrating thermoelectric with Photovoltaic technologies. This research project is run in collaboration with Glasgow University (PI), Exeter and Manchester Universities. Research outputs are regularly discussed with the extensive Industrial Advisory group.
The European project, THERELEXPRO, deals with thermoelectric heat recovery from low temperature exhausts of steel processes. The research undertaken is in collaboration with leading steel manufacturers - CSM (Italy), BFI (Germany), Ferriere Nord (Italy) and AcelorMittal (Spain).
Collaboration with Dana Canada Corporation involves the integration of thermoelectric modules with heat exchangers. Optimisation through computer modelling and precise module assembly to maximise the performance of the thermoelectric modules and heat exchangers to ultimately improve the fuel efficiency of automotive engines. Johnson Matthey, Caterpillar Inc and Ricardo Group are partners in this project.
THERELEXPRO involves characterisation of thermoelectric modules and design, construction and evaluation of thermoelectric systems for industrial partners. Thermoelectric generator prototypes are tested for optimum performance at the university facilities. The prototypes are then installed at the industrial partner’s chosen location for testing under actual operating conditions. Scientific knowhow of thermoelectric technology is shared with the industrial partners on a regular basis.
A Ser Cymru National Research Network grant in Advanced Engineering and Materials is also active in the area of enhanced solar energy harvesting. Collaboration exists between Swansea University, IQE plc and Bangor University.
Other collaborators are European Thermodynamics Limited, and Exeger, who are the industrial partners in the Globasol project which is looking at the commercialisation of solar cells and related technologies.
To meet the challenges associated with energy and power magnetics, the Wolfson Centre for Magnetics is involved in a number of research projects. These include:
- Study of the magnetic behaviour of electrical steels
- Improving efficiency and noise in transformer cores
- On-line production monitoring and process control
- Modelling and prediction of magnetic properties
- Characterisation of magnetic materials under wide-ranging physical and electrical conditions
- Application of magnetic materials in power magnetic devices
Material synthesis and processing
- Spark Plasma Sintering (HP D 10-SD, FCT Systeme)
- Pulsed Laser Deposition (PLD2000, PVD Products)
- Ball Milling (Pulverisette 5 & Spex 8000)
- High Power Ultrasonic Milling (1000W, Hielscher)
- Freeze Casting (Freeze Dryer 85, Lablyo)
- Schlenk line system for nanoparticle synthesis
- Spin Coater (WS 650, Laurell)
- Cutting and Grinding (Accutom 100, Struers)
- Glovebox (Saffron Scientific Equipment)
- High temperature annealing furnace (Carbolite)
- Vibrating Sample Magnetometer (Lakeshore)
- Magnetic Property Measurement System (Quantum Design)
- Physical Property Measurement System (Quantum Design)
- Magnetic Force Microscope (Digital Equipment)
- B-H Loop (MESA, SHB Instruments)
- AC characterisation system for soft magnetic materials (custom)
- DC permeameter for soft and hard magnetic materials (custom)
- Environmental chamber for high-low temperature measurements (Carbolite)
- 100kN stress bed for use with above measurements (Instron)
- Magnetostriction measurement system for lamination materials (custom)
- Transformer test facility (acoustic and 3 axis vibration measurements) (Custom)
- High speed magnetic domain observation system (custom)
- PPMS (thermoelectric properties, Quantum Design)
- Infrared Microscope (Infrascope III, Quantum Focus)
- High-throughput Thermoelectric Measurement System
- Contact resistance scanning probe
- Thermoelectric Impedance Spectroscope (Autolab)
- Thermoelectric Module Evaluation System
- COMSOL (AC, Heat transfer, Thermoelectric, Ray Optics)
Photovoltaic and photonic characterisation
- Solar Simulator and I-V tracer (LCS 100, Oriel)
- Impedance Spectroscope (Metrohm Autolab)
- Spectroradiometer (300nm-1700nm, StellarNet)
- Durability Life-time Testing System