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School of Materials

Studentships and scholarships

Ceramics and Glasses

Your Options

Full-time and part-time programmes are available for most of our research degrees. Split-site degrees are also available, subject to provision of an appropriate study plan, and local facilities and supervision. This allows you to conduct part of your study at a local site near your workplace with supervision from staff in our school. Please contact the School for further information about the Split-site option.

For a full list of qualifications available in the School please see

Projects currently available in this area are listed at below. Applicants are also invited to submit their own project proposal if they wish to work in a specific area for which a project is not currently listed.

Current Projects

For more details about all of these projects, you may download this document

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Current Project Details

Ferroelectric Ceramics for Pyroelectric Energy Harvesting

Pyroelectric materials provide a potentially useful source of power from thermal energy harvesting devices. Unlike conventional thermoelectric materials, which utilise a physical temperature gradient, pyroelectrics can extract energy from fluctuations in temperature over time. Recent research has established that ferroelectric ceramics are the preferred choice of materials for pyroelectric energy harvesting. Furthermore, it has been shown that the performance of such devices can be optimised by making use of thermal and electric field-induced phase transformations, during which the variation in electric polarisation can be enhanced by structural changes within the material. The aim of the project will be to investigate the origins of the polarisation changes in the vicinity of a phase transformation for various types of ferroelectric ceramics. This information will be employed to identify the optimum materials and operating conditions for pyroelectric energy harvesting. A number of different types of phase transformation will be explored, including ferroelectric-ferroelectric, ferroelectric-paraelectric and ferroelectric-antiferroelectric. The contributions to polarisation changes from intrinsic (crystal structure) and extrinsic (ferroelectric domain related) factors will be investigated using a variety of electrical (ferroelectric hysteresis, pyroelectric, dielectric) and structural (XRD, neutron diffraction) measurement techniques.

The following figure illustrates the temperature-dependent change in polarisation for a lead zinc niobate-lead titanate single crystal, as determined by Hajjaji et al. (Acta Materialia 57, 2243, 2009).

Supervisor: Dr David Hall

Phase Switching Behaviour in Lead-Free Piezoelectric Ceramics

Piezoelectric ceramics, typically based on PZT (lead zirconate titanate) serve as the basis for a diverse range of electromechanical sensors and actuators. Changes in legislation and the associated need to reduce the use of lead in many applications have led to a resurgence of interest in lead-free ferroelectric ceramics. To date, the most promising lead-free piezoelectric ceramics have chemical compositions based on the sodium potassium niobate and sodium bismuth titanate systems. Recent reports have suggested that the largest electric field-induced strain in such materials can be produced through a field-induced phase transformation, sometimes referred to as phase switching. The aim of the project will be to explore the factors that influence such phase-switching behaviour and use this as a guide to select materials that might be suited for use in electromechanical actuators. Experimental work will involve the fabrication of candidate ceramic materials and in-situ studies of phase switching by high energy synchrotron XRD, combined with other electrical and structural characterisation techniques (ferroelectric hysteresis, dielectric measurements, SEM and conventional XRD).

The following figure shows a view of the crystal structure of sodium bismuth titanate, presented as part of a review on lead-free ceramics by Aksel and Jones (Sensors 2010, 10, 1935-1954, http://www.mdpi.com/journal/sensors).

Supervisor: Dr David Hall

High temperature mechanical properties of electroceramics

Whilst electroceramic are exploited primarily for their interesting electrical (variable conduction, ionic, piezoelectric, field dependent etc) behaviours, it is still necessary for them to have sufficient mechanical integrity to survive in their chosen environment. A knowledge of materials strength, toughness and internal stress state as a function of temperature is essential in this regard.  Many electroceramics are operated at elevated temperatures under reducing/oxidising conditions, or undergo phase transformations that give rise to strength anomalies. Knowledge of these in the chosen system will enable more resilient structures to be manufactured and allow accurate prediction of component lifetimes to be made based on stress analysis. A research project in this area will address key issues of microstructure and functional performance optimisation, mechanical stability under operating conditions, and processing for device manufacture, using our chemical processing, electron optical and mechanical testing laboratories, with the aim of improving our fundamental scientific understanding of factors affecting the performance and lifetime of these materials in real applications.

Supervisor: Dr Colin Leach

Ionic conductors in energy conversion and gas separation applications

The properties of ionically conducting and mixed electronic/ionic conducting electroceramics are exploited in a range of new and emerging energy efficient technologies including: solid oxide fuel cells for the conversion of fossil fuel to electrical energy at high efficiency, high temperature electrolysis for hydrogen generation from water, oxygen separation membranes for the extraction of oxygen from air, and catalytic partial oxidation reactors for the industrial production of e.g. methanol from hydrogen. A research project in this area will address key issues of phase chemistry and microstructure optimisation, functional performance, stability under extremes of operation, and processing for device manufacture, using our chemical processing, electron optical and electrical testing laboratories, with the aim of improving our fundamental scientific understanding of factors affecting the performance and lifetime of these materials in real applications.

Supervisor: Dr Colin Leach

Grain boundary controlled electroceramics for power dissipation and device protection

Electroceramics such as positive temperature coefficient of resistance thermistors (based on doped BaTiO3) or varistors (based on doped ZnO, SiC, or SnO2) are used in their millions to protect domestic and industrial electrical equipment from power surges and voltage spikes. In both cases the functionality is controlled by changes in the conductivity of the grain boundaries in response to phase transformations, or external electric fields. Thermistors and varistors need to switch between high and low conduction states reliably many times during their life, while dissipating hundreds of Joules of energy. For this reason improvements to materials stability as well as mechanical integrity are of paramount importance Tuning the precise electrical response to match the specific application is necessary to improve device efficiency and hence life.  Additionally PTC thermistors frequently contain lead to increase the switching temperature, but recent legislation has made it necessary to search for greener alternatives. A research project in this area will address key issues of microstructure and functional performance optimisation, stability under extremes of operation, and processing for device manufacture, using our chemical processing, electron optical and electrical testing laboratories, with the aim of improving our fundamental scientific understanding of factors affecting the performance and lifetime of these materials in real applications.

Supervisor: Dr Colin Leach

Study of performance of thermal barrier coatings used for aeroengines

The aim of the project is to study the degradation of thermal barrier coatings which is used for thermal protection of underline metal substrates in harsh high temperature engine environment. The project will involves close collaboration between Manchester University, Rolls-Royce and Production Technology Centre (PTC) ,University of West, Sweden. The goal of the research is to prolong lifetime of the engine components and raise the operation temperature of the aero-engine, therefore, increase the running efficiency of the engine. The samples to be studied will be provided by Rolls-Royce and PTC at Sweden. The techniques used for study include electron microscopy, nano- and micro- indentation, Raman spectroscopy and X-ray tomography. The student will have intensive interaction with the colleagues working in Rolls-Royce and PTC.

Supervisor: Professor Ping Xiao

Novel Fabrication of Thermal Barrier Coatings for Engine Applications

The project will involve close collaboration with Rolls-Royce, Teers Coatings and Mel Chemicals. The aim of the project is to develop electrophoretic deposition (EPD) to produce thermal barrier coatings on engine components. EPD is a simple, easy and cost-effective technique, which allows control of microstructure of ceramic coatings to enhance both mechanical and thermal properties of the coating. The group has worked with a number of industrial companies for about 10 years to develop such technique for industrial application. The focus of this project is to produce ceramic coatings with high temperature stability and mechanical integrity. The research will involve colloidal processing of ceramic coatings, low temperature sintering and mechanical and thermal characterisation of the ceramic coatings.

Supervisor: Professor Ping Xiao

Ceramic coatings on nuclear fuels

The project intends to develop ceramic coatings for nuclear fuels used in a generation IV reactor: high temperature reactors. The function of the ceramic coating is to contain the nuclear fuels during nuclear reaction to allow safe operation of the nuclear reactors even in an accident scenario. Therefore, the mechanical properties and thermal chemical stability of ceramic coatings, eg, SiC and ZrC, will be the focus of this research. In this research, chemical vapour deposition, developed by the the ceramic coating group, will be used to produce both SiC and ZrC coatings. In addition, nano-indentation will be used to measure the mechanical properties of the coatings and electron microscopy coupled with Raman spectroscopy will be used to examine the microstructure and composition of the coatings. The goal of this research is enhance the operation temperature and allow absolutely safe operation of such reactors.

Supervisor: Professor Ping Xiao

Microwave Dielectric Ceramics for Mobile Telephone Applications

Temperature stable dielectrics are crucial components in mobile telephone systems. In recent years, complex perovskites, including Ba(Zn1/3Ta2/3)O3  (BZT)-based ceramics, have been favoured for resonators in base stations for mobile telephone systems because of their temperature stable dielectric properties, moderately high relative permittivity (er) and exceptionally low dielectric losses (more conveniently described in terms of very high Q value of ~80000 at 2 GHz).  The explosive rise in the price of Ta2O5 means that (BZT) based materials are no longer economically attractive and alternatives are being sought. Complex perovskite-based niobates have been used in recent years. We now wish to investigate niobate-based microwave dielectrics of different structures which can be processed at lower temperatures but still exhibit excellent properties. Recent work in the School of Materials has demonstrated that excellent microwave dielectric properties can be achieved with columbite and perovskite structure niobate ceramics. The objective of the project is to investigate the properties of columbite-structured and niobates that can be fired at low temperature, suitable for the next generation of microwave dielectrics.Niobate-based ceramics will be prepared by a mixed oxide route. Starting powders and calcined powders will be characterised in terms of morphology (scanning electron microscopy) and phase development (X-ray diffraction). High density ceramics will be produced under a variety of sintering temperatures and processing conditions. The products will be assessed in terms of densification, microstructure development (scanning electron microscopy), phase development (X-ray diffraction) and electrical properties at both low frequency and microwave frequencies. Raman spectroscopy will be used to gain information about loss mechanisms in the materials, and TEM techniques for information about sub-grain structures. The primary objective is to understand how processing conditions and composition can be used to engineer the microstructure and final properties

Supervisor: Professor Robert Freer

Low Temperature Nanostructured Oxide Thermoelectrics for Power Generation

There is growing concern over the consumption of fossil fuels and resulting carbon emissions, particularly in automobile and power generation systems. One possible way forward is Thermoelectric (TE) technology, which involves the direct conversion of waste heat into electric power. This has the advantage that it does not involve chemical reactions and no moving parts. The efficient conversion of heat into electricity requires the development of functional materials with a high figure of merit, defined by Z = S2/rk, where S is the Seebeck coefficient, r is electrical resistivity and k is thermal conductivity. Many traditional TE materials including Bi2Te3, PbTe have been available for over 50 years, but tend to have maximum operating temperatures of 400-600K. Skutterudites appeared in the 1990s, with CoAs3-type structures as medium temperature TE materials.   However, toxicity and limited temperature of operation mitigate against their exploitation. There are now real opportunities for ceramic thermoelectrics which can operate over a wide range of temperatures. Novel oxides are attractive as components for both low temperature (domestic applications) and high temperature (industrial and transport) applications. Oxide ceramics will be prepared by a mixed oxide and chemical routes, using selected additives. This will involve mixing, milling, pressing and sintering. Starting powders and ceramic products will be characterised in terms of morphology (scanning electron microscopy) and phase development (X-ray diffraction). High density ceramics will be produced under a variety of sintering temperatures and processing conditions. As the strategy is to reduce the electrical resistivity and thermal conductivity to enhance thermoelectric performance, particular attention will be paid the relationship between microstructure (SEM/TEM analysis), electrical properties and thermal properties. The thermal diffusivity will be measured by the laser flash technique and specific heat measured to yield thermal conductivity data. Detailed X-ray diffraction work will be undertaken to understand structural changes as a function of composition. The objective is to understand how the nanostructure can be manipulated to give the desired improvements in thermoelectric performance.

Supervisor: Professor Robert Freer

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