SusMat0 research projects and industry partnerships

Ideal electrolytes for energy devices such as batteries and solar cells would (i) be lightweight and flexible, (ii) exhibit thermal stability, (iii) be non-volatile (to reduce fire risk), (iv) provide good interfacial contact with electrodes, (v) be amenable to processing and recycling, (vi) have high ionic conductivities, and (vii) be made from cheap, renewable feedstocks. There are currently no electrolytes (inorganic solids, organic liquids, or composites) that meet all these criteria simultaneously.

This PhD project aims to develop a series of electrolytes that meet these criteria. In particular, we aim to use organic and supramolecular chemistry concepts to design electrolytes that retain liquid-like ionic conductivity in the solid state, i.e., they act as state-independent electrolytes. The project is suited to students who have interests in organic materials chemistry and synthesis, and who are excited by working in an interdisciplinary team.

The student will be trained to carry out the organic synthesis of state-independent electrolytes and to characterise their conductivity and other materials properties under the supervision of Dr McGonigal in the Department of Chemistry. Their experiments will be guided by simulations of the ionic conduction, which the student will learn to perform under the guidance of Prof Probert in the School of Physics, Engineering and Technology.

The studentship is offered by the Centre for Doctoral Training in Sustainable Materials for Net Zero (SusMat0). SusMat0 is focused on the development of sustainable materials for advanced energy-related technologies key to achieving the target of net zero carbon emissions. It includes research on materials for energy generation/storage technologies (for example solar cells, batteries), devices with improved energy efficiency (for example OLEDs, memories, power electronics) and technologies for synthesising chemicals using renewable energy. As a member of a cohort of students you will receive training in core chemistry, physics and engineering approaches relevant to cross-disciplinary sustainable materials research. We aim to produce well-rounded scientists, equipped and empowered to engage effectively with each other.

School of Physics, Engineering and Technology

Professor Keith McKenna, Dr Mahmoud Dhimish

Solar photovoltaics (PVs) now account for close to 4% of global electricity generation, with installed capacity growing almost exponentially. Cracks in PV panels caused by mishandling during installation or mechanical stress are ubiquitous but poorly understood problems impacting the performance and sustainability of PV technology. Recently we have highlighted the role of cracks and associated bond breaking in the formation of hotspots, accelerated efficiency degradation and panel failure in current-generation crystalline silicon panels [1]. However, the effects of cracks in prospective next-generation PV materials are so far unexplored.

Polycrystalline chalcogenide and halide perovskite solar absorbers are strong candidates for next-generation PV devices that will support the sustainable growth of capacity. Intriguingly, our recent materials modelling investigations have shown that many of these materials are intrinsically more robust against the rupture of bonds (for example, at surfaces and grain boundaries) than silicon [2,3]. Could some of these materials therefore be more tolerant to mechanically induced cracks? This project aims to investigate this question through predictive materials modelling and complementary experimental device characterisation to help identify the most promising crack-tolerant PV materials.

In this project, density functional theory will be employed to investigate the effect of crack formation on electronic properties in a range of PV materials (Si, CdTe, Sb2Se3 and halide perovskites). The interaction of the exposed crack with adjacent layers in the device and the external environment (in case the encapsulation fails) will also be explored. Complementary experimental investigations will be carried out on PV devices (provided by collaborators) using mechanical bending to initiate crack formation together with structural, electrical, electro/photo-luminescence, and thermal-imaging characterisation.

[1] M.Dhimish et al., Sci. Rep. 11, 23961 (2021)

[2] K.McKenna, ACS Energy Lett. 3, 2663 (2018)

[3] K.McKenna, Adv. Electron. Mater. 7, 2000908 (2021)

If you have any enquiries, please email Professor Keith McKenna

Applications for this studentship will be considered on a first-come, first-served basis and the position will be filled as soon as a suitable applicant is identified.

Apply for this project

School of Physics, Engineering and Technology

Professor James Walsh, Dr Thomas Farmer, Dr Yihua Hu

Plastics are a cornerstone of society, yet plastic waste is an environmental tragedy. Each year 370 million metric tons of plastic are produced, 79% of which is used once and discarded. With global plastic production capacity set to double before 2040, there is an urgent and as yet unmet need to improve sustainability.

Composite plastic materials, comprising of multiple layers of different polymers, are used ubiquitously across all sectors, yet they are extremely challenging to recycle. This studentship will explore a novel plasma-based approach to deposit thin functional coatings on polymeric films, creating a material that offers the benefits of a composite with the recyclability of a monolayered material. Success in this area would be transformative, vastly reducing the energy and material costs associated with plastic production and recycling. To achieve this goal will require a top-class student supported by a cross-disciplinary team of experts, drawing on domain leading knowledge in plasma physics, engineering and green chemistry.

The project will be conducted in three phases, each having the capacity to deliver quality scientific outputs:

Phase (1) physical and chemical characterization of an atmospheric pressure plasma roll-to-roll polymer treatment system - Initially, the appointed student will be trained in the use of advanced optical diagnostic techniques to assess the physicochemical properties of low temperature plasma interacting with a moving polymeric film. This activity will involve the use of Laser Induced Fluorescence techniques to quantify reactive species within the plasma and Particle Image Velocimetry to assess the impact of gas flow on the uniformity of species arriving at the polymer substrate.

Phase (2) Linking polymer characteristics to plasma parameters – Understanding the complex link between plasma parameters and the resulting physical/chemical changes of the exposed polymer is vital for the development of advanced functional materials. The student will be trained in a host of advanced surface diagnostic techniques (e.g. Fourier Transform Infrared, Atomic Force Microscopy, X-ray photoelectron spectroscopy and Nuclear Magnetic Resonance) enabling the link between plasma parameters and the characteristics of exposed polymer materials to be understood.

Phase (3) Exploration and optimisation of novel plasma functionalised films with industry relevance – The understanding gained in phases 1 and 2 will be exploited to create a host of novel polymeric materials that offer the advantage of a multilayer composite material with the recyclability of a monolayered film. Efforts will be directed towards understanding how the novel plasma created materials degrade with time compared to conventional multi-layered materials commonly used in food packaging applications.

If you have any enquiries, please email Professor James Walsh

School of Physics, Engineering and Technology

Professor Vlado Lazarov, Dr Richard Douthwaite, Professor Keith McKenna

Titanium dioxide (TiO2) plays a critical role in advanced technologies for green energy and a clean environment. As a photocatalyst TiO2 is used in several applications, including gas pollutant removal ie NOx and CO2, wastewater remediation, and recently as an antiviral and antibacterial agent. TiO2 satisfies all the main criteria for use at large-scale; it is cheap, non-toxic and environmentally friendly, as well as structurally stable and abundant. Besides these advantages, the main challenge of TiO2 as a photocatalyst for H2 production is the low efficiency due to limited light absorption and rapid e-/h+ recombination. This project aims to address these challenges of using TiO2 for H2 production (1) control of nanoparticle size and crystallinity, (2) surface and morphology modifications by addition of cocatalysts.

The transformative potential of this project consists of the combination of synthesis /growth of TiO2 nanoparticles and films, modelling of electronic and optical properties, and state-of-the-art in- operando and in-situ atomic level characterisation that would be performed by utilising the environmental aberration-corrected TEM capability at the York-JEOL Nanocentre, which is a novelty. The latter supports the introduction of gas and/or light allowing nanoscale imaging and spectroscopy. This highly innovative approach, and will be undertaken for the first time, with the objectives of (1) enhanced photocatalytic activity of TiO2-cocatalyst systems by improving light absorption and (2) understanding the mechanisms/structures that lead to improved catalyst/cocatalyst systems.

The prospective student will be trained and take an integral part in synthesis, atomic-level characterisation as well as modelling. This will allow the student to be involved in all aspects of the project, from designing experiments to sophisticated data analysis supported by quantum mechanical calculations. This approach will produce a well-rounded researcher in the field of H2 production, an important venue for meeting Net Zero targets.

If you have any enquiries, please email Professor Vlado Lazarov

Department of Chemistry

Dr Alyssa-Jennifer Avestro, Professor Keith McKenna

Metal–organic frameworks (MOFs) are intrinsically porous extended solids formed by coordination bonding between organic ligands and geometry-directing metal ion clusters. Since the inception of the field in the late 1990s, these materials have been investigated extensively for applications in gas storage, separations, and catalysis because of their high porosity and chemical tunability. However, high electrical conductivity is rare in MOFs, even though this property would enable diverse sustainable technologies in charge (energy) storage and electrocatalysis, among others. Indeed, the electronic properties of MOFs have received comparatively less attention than their physical MOF properties until recently, driven by renewed commitments to global sustainable energy agenda. However, timely progress in the field still faces potential barriers given that the study of these gateway materials are often siloed to single disciplinary approaches: whether by theoreticians (who model conductivity and transport dynamics), synthetic chemists (who engineer intrinsic electronic properties through bottom-up molecular design) and materials scientists (who measure physical material properties and the performance of MOFs within solid-state applications).

The project aims to establish rational design principles for electrically-conductive and redox-active porous organic framework materials towards achieving sustainable semiconductor and energy storage technologies. By pursuing a holistic experimental and theoretical understanding of fundamental properties, this project will adopt a “model–make–measure” approach via oversight of a single, well-trained SusMat0 PhD researcher led by an expert supervisory team across Chemistry (Avestro) and the School of Physics, Engineering and Technology (McKenna) at the University of York. By positioning the lead PhD researcher strategically at the heart of both experimental and theoretical activities, we maximise their project oversight and eliminate communication barriers that can hamper traditional cross-disciplinary collaborations between theoretical physicists and experimental chemists, thereby facilitating the vision and potential for research impact.

In Year 1, they will immediately undertake training in both Departments to design, prepare and model electrically conductive MOFs comprising electrochemically active organic linkers based on well-established aromatic diimide charge acceptors and conductive transition metals like iron/copper/cobalt/manganese. First-principles modelling approaches will enable the student to identify the predominant conductivity pathways at the molecular/nanoscopic levels for MOFs being simultaneously prepared and optimised. As novel materials are generated, first-principles modelling will become further useful in Years 2–3 for correlating grain boundary influence on bulk properties, as determined experimentally by electron microscopy (JEOL Nanocentre), materials analysis (Green Chemistry) thin-film X-ray diffraction (Chemistry), and semiconductor and battery device testing (Chemistry). Promising project materials to be integrated within rechargeable batteries and electrochemical devices, utilising the expertise of the lead supervisor. As a result, the PhD researcher will gain a broad and diverse skill set in materials synthesis, physical and electronic properties characterisation, device fabrication and testing, and theoretical modelling of intrinsic conduction pathways. This concerted cross-disciplinary effort will ultimately aid our ability to overcome the current limitations in conductive MOF research, raising the probability of innovation in sustainable energy technologies from York.

If you have any enquiries, please email Dr Alyssa-Jennifer Avestro

Mahmoud Dhimish (Primary Supervisor), Vlado Lazarov (Secondary Supervisor)

Project Description:

An exciting PhD opportunity is open at the University of York, Centre for Doctoral Training (CDT) in Sustainable Materials for Net Zero (SuMat0), where the appointed researcher will be instrumental in forging new pathways for recycling solar photovoltaic (PV) materials. The project will tackle the complex challenge of sustainably managing end-of-life PV panels through the development of advanced recycling processes that bridge the gap between academia and industry standards.

Research Methodology:

The methodology adopted for this PhD project is a comprehensive approach that synthesises chemical and thermal treatment strategies to recover and repurpose materials from PV modules. The student will design and execute a series of experiments beginning with:

Chemical Leaching Techniques: The researcher will implement an innovative two-stage leaching process. The primary stage will focus on the solubilisation of aluminium using a carefully prepared solution, optimising the concentration, temperature, and time to maximise yield. The secondary stage will be dedicated to the recovery of silver, employing an organic solvent mixture to dissolve and subsequently precipitate silver chloride, a valuable material for reclamation.

Optimised Thermal Treatments: In parallel, the candidate will develop thermal treatment protocols to disassemble the PV modules and separate the encapsulant from the glass and silicon layers. They will explore different temperature profiles and atmospheres to determine the most effective conditions for material separation that prevent degradation and facilitate the reuse of silicon and glass in new modules.

Material Characterisation and Analysis: Post-treatment, the candidate will utilise a battery of analytical techniques. Advanced microscopy methods like TEM and SEM will be used to assess the morphology and composition of reclaimed materials. AFM will provide nanoscale surface characterisation, vital for understanding the structural integrity of recycled silicon wafers. Additionally, the project will incorporate EL/PL imaging techniques to assess the optoelectronic quality of the silicon material, essential for determining the efficiency potential of recycled PV cells.

Throughout this experimental phase, the student will be expected to fine-tune process parameters to improve the efficacy and environmental footprint of the recycling process. A life cycle assessment will be conducted to ensure the new methodologies not only meet the standards for material recovery but also contribute positively to the overall sustainability of the PV industry. It is the goal of this approach to achieve >95% glass reuse, >90% metal recovery, and up to 85% silicon reuse. As a result, nearly 85% of the PV materials can be extracted efficiently in this way, which is in alignment with the current EU/UK WEEE regulations.

Project Impact:

The expected outcome of this research would be the creation of a scalable, economically feasible, and environmentally friendly PV recycling protocol. Not only will this alleviate the growing waste management problem, but it will also create a blueprint for future research and development regarding the treatment of PV end-of-life materials in a sustainable way.

Application Process:

Candidates with a background in engineering, physics, materials science, chemistry, or a related field with industrial experience are encouraged to apply. Please submit your CV, a cover letter detailing your research interests and experience, and at least two academic or professional references.

Join us in developing the next generation of sustainable PV recycling technologies and make a lasting impact on the future of renewable energy!

Centre for Doctoral Training in Sustainable Materials for Net Zero (SusMat0)

The studentship is offered by the Centre for Doctoral Training in Sustainable Materials for Net Zero (SusMat0). SusMat0 is focused on the development of sustainable materials for advanced energy-related technologies key to achieving the target of net zero carbon emissions. It includes research on materials for energy generation/storage technologies (for example solar cells, batteries), devices with improved energy efficiency (for example OLEDs, memories, power electronics) and technologies for synthesising chemicals using renewable energy. As a member of a cohort of students you will receive training in core chemistry, physics and engineering approaches relevant to cross-disciplinary sustainable materials research. We aim to produce well-rounded scientists, equipped and empowered to engage effectively with each other.

For any informal inquiries about this project, please contact Dr. Mahmoud Dhimish, the primary supervisor, at Mahmoud.Dhimish@york.ac.uk 

Ideal electrolytes for energy devices such as batteries and solar cells would (i) be lightweight and flexible, (ii) exhibit thermal stability, (iii) be non-volatile (to reduce fire risk), (iv) provide good interfacial contact with electrodes, (v) be amenable to processing and recycling, (vi) have high ionic conductivities, and (vii) be made from cheap, renewable feedstocks. There are currently no electrolytes (inorganic solids, organic liquids, or composites) that meet all these criteria simultaneously.

This PhD project aims to develop a series of electrolytes that meet these criteria. In particular, we aim to use organic and supramolecular chemistry concepts to design electrolytes that retain liquid-like ionic conductivity in the solid state, i.e., they act as state-independent electrolytes. The project is suited to students who have interests in organic materials chemistry and synthesis, and who are excited by working in an interdisciplinary team.

The student will be trained to carry out the organic synthesis of state-independent electrolytes and to characterise their conductivity and other materials properties under the supervision of Dr McGonigal in the Department of Chemistry. Their experiments will be guided by simulations of the ionic conduction, which the student will learn to perform under the guidance of Prof Probert in the School of Physics, Engineering and Technology.

The studentship is offered by the Centre for Doctoral Training in Sustainable Materials for Net Zero (SusMat0). SusMat0 is focused on the development of sustainable materials for advanced energy-related technologies key to achieving the target of net zero carbon emissions. It includes research on materials for energy generation/storage technologies (for example solar cells, batteries), devices with improved energy efficiency (for example OLEDs, memories, power electronics) and technologies for synthesising chemicals using renewable energy. As a member of a cohort of students you will receive training in core chemistry, physics and engineering approaches relevant to cross-disciplinary sustainable materials research. We aim to produce well-rounded scientists, equipped and empowered to engage effectively with each other.

Department of Chemistry

Dr Richard Douthwaite, Professor Vlado Lazarov

As wind and solar energy continue to make an increasing contribution to our electricity supply there is a growing need for effective storage to balance demand. Renewable energy storage in a chemical fuel is one option that could also make a significant contribution to some transportation needs particularly if coupled with CO2 capture and utilization. However, catalysts are required for chemical fuels synthesis using intermittent energy, which can operate with repeated cycling without degradation. This contrasts with the continuous steady-state processes typically used in industrial chemicals production. Recent developments in aberration-corrected environmental transmission electron microscopy (AC-eTEM) allow dynamic in-operando investigation of catalytic reactions with atomic precision.

We aim to use state-of-the-art AC-eTEM for dynamic in operando studies of catalysts used for CO2 to fuels. Specifically, iron catalysts are used for the hydrogenation of CO2 giving carbon coupled products. However, catalyst lifetime and product selectivity are key challenges, resulting from catalyst evolution due to structural and compositional changes, particle sintering, and coking. We aim to gain an atomic understanding of catalyst evolution in operando as a function of reactive gas atmospheres and temperature to help target catalysts resistant to repeated cycling and improve selectivity for carbon coupled products from waste CO2. A student will gain knowledge of the hydrogen economy, CO2 mitigation strategies and expertise in catalysis and advanced electron microscopy methods. As part of a cohort of students under SusMat0 further broader experience will be gained across materials synthesis, characterisation and modelling applied to meeting Net Zero targets.

If you have any enquiries, please email Dr Richard Douthwaite

Apply for this project

Department of Chemistry

Professor Andrew Weller, Dr Christina Wang

This new cross-disciplinary project brings together innovative main-chain boron-nitrogen polymer synthesis with advanced nanolithography techniques to make novel, efficient, energy storage systems. These three areas were unconnected until Poly-CAP.

High-performance capacitors have enormous potential as efficient rechargeable power sources, as compared with batteries their attenuated chemical decomposition mechanisms favour fast charge-discharge rates and long-term stability. An ideal capacitor material would have the combined characteristics of low dielectric constant , high breakthrough current, low conductivity and wide band-gap; as well as thermal, chemical and mechanical stabilities. The ability to manufacture such materials on scale, having well-resolved interdigitated electrodes with high surface area is also crucial. Chemically and thermally robust hexagonal boron nitride (h-BN) is one such material that shows significant promise (<4, band gap >6ev), which is also tuneable by the incorporation of dopants such as carbon or nitrogen. However, many of the current manufacturing routes are “top-down” using preformed h-BN, making precise surface engineering, chemical modification, and thus optimisation, challenging.

In this proposal a molecular “bottom-up” methodology will be developed to manufacture high-performance h-BN based thin-film capacitors, that brings together complementary expertise of Weller (advanced main-group polymers) and Wang (nanotechnology and nanomaterials). Efficient routes to chemically tuneable, recyclable, main-group B/N polymeric precursors (polyaminoboranes) [1] will be combined with advanced fabrication techniques (nanoimprinting, electron beam etc.) [2] to produce high surface area, thin-film h-BN capacitors. The project will specifically involve targeted catalytic atom-efficient synthesis (dehydropolymerisation) of known and new polyaminoboranes, [H2BNRH]n, and their subsequent deployment as atomically precise precursors for subsequent device fabrication. This is a new approach to BN containing capacitors and will offer the advantages of controllable precursor chemical composition/stability, precise patterning, and opportunities for manufacturing scale-up.

[1] J.Am.Chem.Soc. 2021, 143, 21010
[2] Sci.Rep. 2016, 6, 1

If you have any enquiries, please email Professor Andrew Weller

Apply for this project

Department of Chemistry

Professor Victor Chechik, Dr Mohammad Nasr Esfahani, Dr Richard Douthwaite

Light and electricity are the most sustainable and efficient energy sources for chemical reactions, and recent years saw an explosion of interest in photo- and electrocatalytic synthetic methodologies. Heterogeneous photocatalysts (eg, inorganic semiconductors) are particularly attractive as they offer simple product separation. However photochemical transformations with semiconductor catalysts often suffer from low efficiency, eg, due to competing electron-hole recombination. Coupling photo and electrocatalysis makes it possible to overcome this issue and significantly improve reaction efficiency.

The efficiency of photo and electrochemical processes can be significantly increased in continuous flow systems, as this decreases the distance between the electrodes and hence resistance losses, reduces light path length and increases surface to volume ratio. While flow electrochemical and flow photochemical processes are well established, there are virtually no reports on flow photoelectrochemistry - despite clear advantages! Developments in this area are thus urgently needed.

In this project, we will design, build and optimise a continuous flow set-up for photoelectrochemical reactions. The new setup will be used to develop energy-efficient synthetic methodologies for the preparation of industrially-relevant chemicals. We are particularly interested in photoelectrochemical C-C bond formation which is critical for the synthesis of advanced materials, pharmaceuticals and agrochemicals. The project will strongly benefit from the combined expertise of the supervisors in the areas of organic and radical chemistry, semiconductor synthesis and characterisation, photo- and electrochemical synthesis, chemical engineering, 3D printing and design and manufacture of complex devices. We anticipate that the new methodology will offer significant benefits for the applied organic synthesis compared to conventional approaches, and will in due course attract industrial interest.

The project is highly interdisciplinary and provides training in a wide range of device design and manufacturing, synthetic organic and inorganic methods, photo- and electrochemistry, and data analysis.

If you have any enquiries, please email Professor Victor Chechik

Apply for this project

School of Physics, Engineering and Technology

Dr Mohammad Nasr Esfahani, Dr Richard Douthwaite, Prof Vlado Lazarov

To achieve the target of net zero emissions, both sustainable materials and advanced energy-related technologies will play important roles. In this context, hydrogen energy is considered one of the most promising for enabling global decarbonization and a clean energy transition. However, the storage, transportation, and processing of hydrogen are critical challenges to develop large-scale use. This is related to the diffusion of hydrogen in materials followed by degradation of properties and premature failure, known as “Hydrogen Embrittlement”, which has a direct impact on the energy price due to downtime and maintenance, or additional costs associated with possible passivation treatments. Hence, a fundamental and predictive physical mechanism is required to reveal the interaction of hydrogen with materials to inform the design of hydrogen-related facilities.

This project aims to provide a predictive mechanism for hydrogen embrittlement in metal crystals – mainly iron as a well-known sustainable material – through addressing the fundamental questions at the atomic scale using a combination of hydrogen diffusion experiments, state-of-the-art environmental transmission electron microscopy, and modelling. Experimental observations will be fed into numerical models to predict the hydrogen mobility in metal crystals and its implications on materials properties. We will collaborate with our commercial partners, JCB, who are a leading company in the use of sustainable machinery, to apply the predictive mechanism toward Hydrogen Internal Combustion Engines (H2-ICEs).

In this project, the student will receive a novel set of training skills on materials characterizations i.e. electron microscopy, mechanical testing, hydrogen- related failure analysis and Raman spectroscopy to test materials in hydrogen-related facilities. These skills will equip the student with knowledge and skills to predict potential hydrogen embrittlement phenomena in materials as well as addressing mitigation plans to improve sustainability. This project will engage with energy-related industrial partners to educate CDT with existing challenges and barriers to improve hydrogen-related technologies.

If you have any enquiries, please email Dr Mohammad Nasr Esfahani

Apply for this project

Department of Chemistry

Dr Paul McGonigal, Professor Matt Probert

Ideal electrolytes for energy devices such as batteries and solar cells would (1) be lightweight and flexible, (2) exhibit thermal stability, (3) be non-volatile (to reduce fire risk), (4) provide good interfacial contact with electrodes, (5) be amenable to processing and recycling, (6) have high ionic conductivities, and (7) be made from cheap, renewable feedstocks. There are currently no electrolytes (inorganic solids, organic liquids, or composites) that meet all these criteria simultaneously.

This PhD project aims to develop a series of electrolytes that meet these criteria. In particular, we aim to use organic and supramolecular chemistry concepts to design electrolytes that retain liquid-like ionic conductivity in the solid state, ie, they act as phase-independent electrolytes. The project is suited to students who have interests in organic materials chemistry and synthesis, and who are excited by working in an interdisciplinary team.

The student will be trained to carry out the organic synthesis of phase-independent electrolytes and to characterise their conductivity and other materials properties under the supervision of Dr McGonigal in the Department of Chemistry. Their experiments will be guided by simulations of the ionic conduction, which the student will learn to perform under the guidance of Prof Probert in the School of Physics, Engineering and Technology.

If you have any enquiries, please email Dr Paul McGonigal

Apply for this project

School of Physics, Engineering and Technology

Professor Matt Probert, Dr Stuart Cavill

Background: Thermoelectric materials (TE) can improve energy efficiency and reduce dependency on fossil fuels, as they convert waste heat into useful electricity using a solid material with no moving parts. The Seebeck effect can operate whenever there is a temperature gradient: the greater the gradient, the more useful power that can be generated. The key challenge is to find a material that can generate a useful amount of power from modest heat sources, without using expensive or toxic elements.

Probert and his group have in recent years developed a complete workflow to predict zT, the key efficiency parameter, for any material from first principles using the CASTEP code. However, the whole process is slow, taking many months to characterise a single material. Ideally, we would have an efficient high throughput method that would enable many potential materials to be evaluated and hence accelerate discovery.

Objectives: The challenge for this PhD is to employ recently developed machine learning (ML) techniques within CASTEP to dramatically accelerate the key bottleneck parts of the calculation. Recent ML developments have accelerated CASTEP molecular dynamics (MD) by 10x. The student will replace the current use of the Boltzmann Transport Equation by MD- based techniques. This is a big change, and so they will first predict zT for some available materials that are not yet known to be thermoelectric, and then test the predictions by using the recently acquired PPMS (Physical Property Measurement System) to measure zT on real samples. Once the ML-accelerated methodology is validated, we can proceed to high-throughput screening to find better TE materials.

Training: The student will be trained by Probert in a variety of first principles simulation techniques and to code to a high standard, and by Cavill in the experimental measurement of transport properties.

If you have any enquiries, please email Professor Matt Probert

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Department of Chemistry

Dr John Slattery, Dr Alison Parkin, Dr Phil Hasnip, Professor Matt Probert

The climate crisis requires us to transform the way that we generate, store and use energy. Two aspects are important for this project: 1) Grid energy storage, e.g. from renewable sources. 2) Shorter-term energy storage technologies, e.g. for electric vehicles. Although these applications are very different, fundamental research into novel electrolytes will deliver enhanced performance and sustainability in both areas.

We recently developed novel redox-active organic salts derived from ionic liquids that can be oxidised and reduced to store/recover energy. They are based on naturally occurring building blocks, contain only earth-abundant elements, are simple to prepare and are readily tunable for specific applications. Their solubilities are excellent and coupled with their favourable redox potentials they will enable energy storage with high energy densities. Thus, they promise to provide enhanced performance, cheaper, non-toxic, more sustainable electrolytes for redox-flow batteries (for grid storage) and hybrid supercapacitors (for electric vehicles). However, fundamental understanding of these salts is lacking, especially on ion-ion and ion-electrode electron transfer processes, but now needed to enable their optimisation.

This PhD project brings together synthetic work, advanced electrochemistry and state-of-the art computational modelling to: 1) Expand and optimise our library of redox-active salts, particularly for redox potentials and physical properties. 2) Perform electrochemical studies, including AC voltammetry and spectroelectrochemistry, to investigate electrolyte redox behaviour and electron- transfer processes at the electrodes. 3) Use high-performance computing and quantum-chemical models to understand organisation and reactivity of ions at the electrode/electrolyte interface and probe electron-transfer processes.

The synergy between theory and experiment will allow unprecedented understanding of these salts. This will identify structural modifications to explore in the lab to improve performance, forming a feedback loop enabling rapid optimisation. Finally, we will develop prototype devices that test the performance of the optimised electrolytes in real systems, followed by IP protection and translation.

If you have any enquiries, please email Dr John Slattery

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Department of Chemistry and School of Physics, Engineering and Technology

Professor Andrew Weller, Dr Christina Yue Wang

The manipulation of light in optoelectronic devices is a cornerstone for the delivery of Net Zero, for example in low-energy optical computing (silicon-photonics) and green hydrogen generation from water (photocatalysis). Underpinning such technologies are 2D/thin-film group III/IV/V semiconductors that have controllable bandgaps. Unlike graphene (zero bandgap) or hexagonal-boron-nitride (h-BN, 6 eV), boron-phosphide (BP) is a semiconductor (2 eV bandgap for cubic-BP, 1 eV direct bandgap predicted for h-BP), that also has additional attractive thermal (conducting), mechanical (super-hard) and chemical (oxidation-resistant) properties. However, c-BP is notoriously difficult to synthesise, while the synthesis of h-BP is unknown. Unlocking the reliable, scalable, and efficient synthesis of c-BP and h-BP will set the scene for their wider development and represent a breakthrough in main-group materials chemistry and III–V semiconductor utilisation for Net-Zero applications. In particular, c-BP is acknowledged as being a next-generation photocatalyst for water splitting (i.e. green hydrogen); while h-BP is predicted to be a perfect candidate for deployment in silicon emitters, the “Holy Grail” of optical computing.

This project will explore the synthesis and development of main-group phosphine-borane-polymers (polyphosphinoboranes) as scalable pre-ceramic precursors to c-BP or h-BP. These polymers will then be integrated with photonic devices, such as solar absorbers and silicon emitters, using thin-film methods and nanolithography techniques. The project will combine the expertise of Andrew Weller in the catalytic synthesis and exploitation of pre-cursor BP-polyphosphinoboranes [1] with expertise in photonic devices of Christina Wang [2].

The project will be suitable for a PhD candidate who has interests in innovative molecular synthesis methods for new, polymeric, pre-ceramic BP-polymers, and their deployment in technologically important photonic devices. The project will be truly interdisciplinary, crossing traditional boundaries. The PhD student would be based in both the Weller and Wang labs, with access to the state-of-the-art facilities including the nanofabrication facility at York JEOL Nanocentre, and will work with teams of experts in both groups to deliver on the ambitious goals. While full training will be given in all aspects of the project, it would best suit a graduate student with experience of synthetic chemistry who has a real interest in transitioning and expanding their skill set to include materials chemistry and device fabrication. There are opportunities for wider collaboration on the project (and international travel) to other centres of excellence in main group polymer synthesis and materials characterisation.

The studentship is offered by the Centre for Doctoral Training in Sustainable Materials for Net Zero (SusMat0). SusMat0 is focused on the development of sustainable materials for advanced energy-related technologies key to achieving the target of net zero carbon emissions. It includes research on materials for energy generation/storage technologies (for example solar cells, batteries), devices with improved energy efficiency (for example OLEDs, memories, power electronics) and technologies for synthesising chemicals using renewable energy. As a member of a cohort of students you will receive training in core chemistry, physics and engineering approaches relevant to cross-disciplinary sustainable materials research. We aim to produce well-rounded scientists, equipped and empowered to engage effectively with each other.

[1] J. Am. Chem. Soc. 2021, 143, 21010; Angew. Chem. Int. Ed. 2023, e202216106

[2] ACS Nano 2022, 16, 6493; Laser Photonic Rev. 2018, 12, 1800015.

If you have any enquiries, please email Professor Andrew Weller.