The projects listed below are available for self-funded MRes (1 year) or international/EU MRes+PhD (4 years) students for October 2017 start. "Home" (UK national) applicants should choose from the list of funded projects. Due to funding restrictions, projects from the funded list are not available to international students. For more information about funding eligibility and scholarships, click here.
The projects listed below are for October 2018 entry.
Projects for Self-Funding Students - MRes or CDT
Mechanically robust, MRI compatible bioelectronics
Cardiac pacemakers consist of three main components; generator, lead and electrode. The lead is the principal cause of both early and late complications of pacing. Approximately 5% of all implanted leads require explanting due to infection, lead dislodgement or mechanical failure. Furthermore, traditional pacemakers are incompatible with magnetic resonance
imaging (MRI) techniques, generating unsafe amounts of heat inside the body.
This project will develop soft, flexible and electrically conductive polymeric materials designed to replace the metal components of pacemaker leads. Electrically conductive elastomers (ECEs) will be developed from composites of conductive polymers (CPs) and elastomeric materials. The project will focus on understanding how to combine these two classes of polymers to create a material capable of meeting the design criteria for flexible bioelectronics. Subsequent work will focus on the design of functional leads with an investigation of processing techniques that do not negatively impact on the ECE properties. Lead and electrodes will be developed in one step, as a continuation of the ECE material, to produce a robust device that carries less risk of fracture failure.
The research outcomes will contribute to the advancement of flexible bioelectronics, primarily focused on the development of stable, MRI compatible pacemaker leads but with clear relevance to a variety of implantable bionic devices.
A student with a polymer chemistry or materials science engineering background would be well suited to this project. Experience with biomaterials or cell culture would be of benefit but is not critical as postdoctoral support and training will be provided for these elements.
For more information, contact Dr Rylie Green: email@example.com
Azoheteroarenes: Next-generation solid-state solar thermal fuels for heat release applications
Considerable effort has been devoted to the development of solar fuels that store the energy of the sun in chemical bonds. An attractive but far less well developed alternative approach would be to harvest and store solar energy in a closed cycle system through the conformational change of molecules that can release the energy in the form of heat on demand. Such solar thermal fuel (STFs) could provide readily integrateable carbon neutral solutions for the provision of heat for a range of personal and industrial heating applications, and would complement other, larger scale, solar thermal conversion processes.
Azobenzenes are molecules that can be photoisomerised from the ground state E isomer to a metastable Z isomer, which subsequently thermally converts back to the ground state; a process with excellent cyclability. Thus, they have long thought to hold potential as STFs. However, there are significant molecular and materials issues for this class of molecules which have hindered their potential and development.
In this project, we plan to exploit a new class of photochromic azo compounds recently discovered at Imperial. Through iterative design-synthesis-characterisation cycles using these scaffolds we aim to develop a pioneering a new class of materials for a range of solid-state STF heating applications.
The ideal candidate shoudl be able to be able to conduct the planned synthesis, characterisation and materials processing required; the student would be expected to hold an undergraduate degree in Chemistry.
For more information, contact Dr Matthew Fuchter: firstname.lastname@example.org
Low band gap acceptors for integrated perovskite/organic solar cell
This project will be focused on the development of low band gap non-fullerene acceptor materials for application in high-performance flexible and printed perovskite/organic integrated photovoltaic cells. To maximize the power-conversion efficiency of integrated solar cells, we will develop wide band gap perovskite and low band gap organic photovoltaic materials to achieve high open circuit voltages and to optimize complementary light absorption. Here we will specifically focus on the synthesis of low band gap acceptors.
This project is a collaboration with Gwangju Institute of Science and Technology.
This project would particularly suit a candidate with a strong interest in applied synthetic chemistry, who likes working in a multi-disciplinary team.
For more information, contact Prof Martin Heeney: email@example.com
IR Detection in Electronic Devices Based on Hybrid Perovskite Materials
Nowadays, infrared light (IR) improves our life through many applications, including non-invasive imaging for medical and security purposes, temperature sensing, and communication. Presently, IR sensors are expensive, so technologies that enable the rapid and cost-efficient detection of IR are needed. One way to produce inexpensive electronic devices is to print them from plastics, however the bandgap of most solution processible materials is too wide to absorb IR light. Same time, bulky IR-absorbing molecules are incompatible with low-cost printing techniques.
This project will research the concept of novel hybrid perovskite-based IR photodetectors that use a two-step process for light detection. The idea relies on our recent observation that some electrons in organic and perovskite electronic devices get ‘stuck’ and cannot move until they receive a ‘kick’ of additional energy. In our detector, visible light or electrical pulses will be used to create a population of immobile electrons in the photodiode material. Then, incident IR photons will be absorbed by intragap optical transitions which will provide additional energy for these electrons to move and generate an electrical current for photodetection.
These novel detectors may bring new functionalities to printable perovskite-based electronics and might allow the integration of cheap and effective IR-sensitive components to existing imaging and communication devices.
The ideal candidate should have background in Physics, Chemistry or Material Science and preferably have some experience in plastic semiconductors, nanofabrication or optical spectroscopy.
For more information, contact Dr Artem Bakulin: firstname.lastname@example.org
Controlled Superstructures in vacuum-deposited Organic Semiconductors
The functionality of organic semiconductor thin film devices depends in most cases to a significant way on the microstructure of the film and the orientation of the molecules. One the one hand, this poses a challenge on the field, on the other hand, the ability to combine materials with very different functional and structural properties in a single device is unique to molecular systems and presents a wealth of opportunities that have so far not been fully exploited.
The goal of this project is to investigate the microstructure of molecular blends and to find ways to obtain regimes favouring isolated molecules, superstructures and phase separated domains. The application focus is on molecular spintronics and organic solar cells, given similar material systems and characterisation techniques, but different microstructural requirements. The PhD student will be able to employ a range of unique in-situ and ex-situ characterisation techniques to determine the microstructure during thin film growth and post-deposition to correlate microstructure with device properties.
Given the close connection of microstructure and device performance for many organic electronics devices, we see many synergies with other PE-CDT research projects and areas of research in organic electronics, as well as high relevance for industry partners.
This project would suit a candidate with a background in Materials, Chemistry or Physics, ideally having done their Master thesis on the microstructural characterization of advanced functional materials.
For more information, contact Dr Sandrine Heutz: email@example.com
Dissolution and sorting of SWNTs for transparent electrodes and thin film transistors
Carbon-based electrodes promise both cheap, printable, flexible, transparent conductors and high performance thin film transistors, crucial for large area plastic electronics. A new process developed at Imperial/LCN/UCL allows dissolution of single-walled nanotubes, without any damaging sonication or oxidation; thus, in principle, very long SWNTs can be dispersed. The process produces charged nanocarbons, which are truly individualised in solution (as shown by neutron scattering), due to electrostatic repulsion. In addition, the charging process can be selective for metallic SWNTs, or semi-conducting SWNTs, and can be used to remove other unwanted impurities. The use of long, metallic nanotubes should provide the required significant improvements in transparent conducting network performance, particularly relevant to flexible electronics. The charge can be neutralised without damage, or exploited to control the deposition process, including creating hybrid composite films, integrating other active device components. The remaining semi-conducting SWNT fractions are of interest for thin film transistors and other PE applications; the LCN approach offers prospects of separating the semi-conducting species by band gap / type.
Our SWNT separation/dispersion technology is already patented and licensed for commercialisation; the extension to further SWNT applications is very timely. Recent important developments in the field, include a two order of magnitude reduction in the price of raw SWNTs, the commercial availability of pure semiconducting SWNTs, and Fujitsu’s recent announcement of a SWNT based memory chip.
The project combines various aspects including an understanding of the physical chemistry of colloidal systems to optimize these unusual inks, materials processing and characterization of thin films, and an appreciate of device physics. The student could have a background in physical/materials chemistry or physics. The emphasis of the project would likely be adjusted to build upon the strengths of the successful candidate.
For more information, contact Prof Milo Shaffer: firstname.lastname@example.org
Flow-based Manufacturing of Non-Fullerene Acceptors
This project seeks to address a key weakness in the field of organic photovoltaics, namely the absence
of quality controlled production methods for organic semiconductors. Using fully integrated flow-based
synthesis procedures, the project aims to provide a controlled method for the production of high
performance non-fullerene acceptors that can be applied to both materials discovery and large-scale (>
100 g/day) manufacturing.
It is essential that the student has demonstrably strong synthetic chemistry skills (through a final year undergraduate project), along with a keen interest in learning flow chemistry. It is desirable, though not essential, for the student to have experience in electronics and software development. This is an industrially focused project, and therefore requires an interest in process scale-up and commercial aspects of chemistry, along with excellent presentation and communication skills.
For more information, contact Prof John de Mello: email@example.com
Engineering stable, high-efficiency perovskite photovoltaics
This project is still available!
The project described builds on existing work within the research group that has formed part if the ICL-GIST GRL. Specifically we propose an approach that focuses on compositional and morphological control of the perovskite active layer material, and importantly, interfacing this with existing and novel charge selective interlayers. We propose detailed structural and compositional characterization (primarily by using analytical tools including TEM, XPS and SIMS) thus exposing the CDT student to state-of-the-art techniques in emerging device platforms.
The development of organic and hybrid interlayer materials, in collaboration with the team at GIST, will allow a focus on tuning electronic properties of the interlayers and to allow some control over reduced degradation in devices. Preliminary results show that simple surface modifications using SAMs/small molecules can have a profound impact on device stability. Additionally using simple deposition methods , controlling the orientation of inorganic interlayers (metal-oxides) can also improve lifetime and stability.
Importantly for the training of the PhD student, key to any successful CDT project, existing relationships will be built upon across the CDT and new collaborations with the research team at GIST will be established and strengthened.
This project is a collaboration with Gwangju Insitute of Science and Technology
This project would particularly suit a candidate with a strong in Materials Chemistry, device fabrication and materials characterization. Obviously a student who is enthusiastic about exchanges to Korea would be desireable.
For more information, contact Dr Martyn McLachlan: firstname.lastname@example.org
Characterisation and design of organic heterostructures for photocatalysis
Development of efficient solar energy conversion technologies for energy generation and storage is critical to future low carbon energy supplies. While solar-to-electric (photovoltaic) energy conversion is widely used, the storage of solar energy in the form of fuels is much less advanced. Photocatalytic fuel generation involves using a light-absorbing material to generate charges that can drive chemical reactions to generate a fuel, such as water photolysis into hydrogen and oxygen. Molecular semiconductors are extremely interesting for this application due to their tuneable, sharp and strong light absorption, low impact fabrication, and opportunity to control surface area.
A key issue is the efficiency of the absorbed photon to charge transfer process. Even in the best functioning organic photocatalytic systems, the quenching of the photogenerated exciton is relatively weak. This stage can be improved through control of the dielectric environment, control of the microstructure of the catalyst, and by use of a heterojunction structure to drive the dissociation of excitons into separated charges. This project will explore the relationship between chemical structure, physical environment and photocatalytic activity of polymer based photocatalysts. Transient optical spectroscopy will be used as a tool to probe the efficiency of photoinduced charge transfer in different conditions. The project will investigate the advantages of using (a) nanostructured materials and (b) heterojunction structures, either based on organic-organic or hybrid organic – metal oxide heterojunctions, in improving photocatalytic activity. In particular we will investigate the trade off between light harvesting and generation of chemical potential when using heterojunction structures .
Organic Near-IR Sensors
supervised by Prof Ji-Seon Kim (Physics, Imperial College) and TBC
Organic sensor devices such as organic photodetectors (OPDs) are important optoelectronic applications using organic semiconductors as a light detecting active medium. OPDs have attracted significant interest in the last two decades due to the possibility for using them for a variety of industrial and scientific applications such as environmental monitoring, communications, remote control, surveillance, and chemical/ biological sensing, with low-cost, light-weight, high efficiency and high environmental friendliness. For OPD applications, it is critical for organic semiconductors to have efficient light harvesting (with high photocurrent and low dark current) and high spectral selectivity (from UV to NIR/IR) properties. Although the rich variety of organic compounds with their absorption spanning from the UV to NIR offers unique possibilities for these required properties, organic semiconductors with a large photoresponse at NIR spectral ranges with efficient light harvesting and air stability are still very difficult to find. In this project, we will develop key fundamental understanding of organic sensor materials and devices towards high-performance and high-stability NIR photodetectors.
For more information, contact Prof Ji-Seon Kim: email@example.com
Organic and Hybrid Thin Films Solar Cells - Energetics and Surface Photovoltage
supervised by Prof Ji-Seon Kim (Physics, Imperial) and TBC
Continuous increase in the device performance of organic and hybrid (including perovskites) solar cells is strongly related to better understanding of optical and electronic properties of the photoactive layer. There are still many electronic processes in organic/organic and organic/inorganic layers that are critical to device performance (e.g. charge carrier generation/recombination, trapping of electrons and holes, and ionic movement) and are not yet fully understood. This project aims to investigate these important electronic processes in terms of their energy levels and the illumination generated surface photovoltage and its transient behaviour. For this, Ambient pressure air photoemission spectroscopy and Kelvin Probe-based surface photovoltage techniques will be used.
For more information, contact Prof Ji-Seon Kim: firstname.lastname@example.org
Circularly polarised photodetectors based on induced chirality in polymer/small molecule blends
Right- and left-handed circularly polarized (CP) light involves photons in the two different spin states. CP light is the basis of long distance optical quantum telecommunication (quantum cryptography), optical quantum computing, and optical spintronics. It can also be used in the detection of chiral biomolecules, including protein folding and chiral molecular labels, and medical tomographic imaging. CP photodetectors are a novel area in organic electronics, allowing the creation of highly compact, integrated devices with advantages over their bulky inorganic counterparts.
To create such organic CP photodetectors, we propose a novel approach involving induced polymer chiroptical absorption (circular dichriosm). This is achieved by blending a (normally achiral) polymer with a chiral small molecule. It will allow the creation of high bandwidth CP photodetectors with tunable wavelength range from the UV through the visible to the NIR using pre-existing high performance polymeric semiconductors. The device performance of CP photoFETs and photodiodes will be explored, along with the optical, electronic and materials properties of the novel chiral polymer/small molecule blends. The project will involve new collaborations with the photonics and nanoplasmonic groups in Imperial Physics, and with the University of Sheffield in developing new fast CP spectroscopies.
This project would suit a student with any applicable physical science/materials science background. Appropriate undergraduate degrees may include Chemistry, Physics, Materials, etc.
For more information, contact Prof Alasdair Campbell: email@example.com