Energy and the Physical Sciences:Beta-enhanced thermionic energy converters and nuclear batteries employing nanostructured diamond electrodes

Lead Research Organisation: University of Bristol
Department Name: Chemistry

Abstract

The waste management and disposal of irradiated graphite from decommissioned Magnox and AGR reactors is a major challenge for the UK nuclear industry. It is estimated that irradiated graphite (~90,000 tonnes) from the UK's decommissioned reactors represents about one third of the current Intermediate Level Waste (ILW) inventory, a significant financial liability. This classification arises from the predicted carbon 14 concentration of irradiated graphite which equates to approximately 40% of the national carbon 14 inventory. The UK nuclear industry is not alone with this irradiated graphite waste management challenge5. It is currently estimated that the global inventory is of the order 250,000 tonnes; with significant quantities in France, Russia, USA and smaller amounts in Japan, Italy, Germany and Spain.
This proposal seeks to address this waste problem and provide a cost effective solution for its disposal; re-cycling the material as a feedstock for a novel type of thermionic energy converter, termed a Beta-enhanced Thermionic Diamond Converter (BTDC).
This proposal will investigate how beta radiation can be used to improve the operating performance of diamond electrode materials and seek to demonstrate a disruptive technology for producing renewable energy at a lower unit cost and with improved efficiency. Concentrated thermal energy can be harvested from numerous sources including Solar, Geothermal and Nuclear. This energy may be converted into electricity by a device called a thermionic energy converter. Such devices were under intensive development in the 1950s and 1960s as a means to power space craft and extract power from nuclear reactors. The performance of these devices was primarily constrained by the lack of a material electrode surface that could exhibit a stable low work function of less than 1 eV. This limited applications of the technology to those that could supply heat at temperatures exceeding 1200 centigrade. Lithiated nanodiamond offers a key part of a potential solution to this technological barrier. It possesses a very large negative electron affinity due to a unique functionalisation of the diamond surface. This surface has a number of beneficial properties including, chemical, temperature stability, high photoelectric yield and low work function. The novel properties of this lithiated diamond surface also make it attractive for applications in radiation detectors, high brightness electron sources, current amplifiers and ion sources. This proposal seeks to maximise the benefits of this diamond material in a thermionic converter: combining it with plasmonic nanostructures to absorb thermal energy, incorporating a beta radiation source to enhance the conversion of heat to thermionic energy.

Planned Impact

The potential beneficiaries of the Beta-enhanced Thermionic Diamond Converter (BTDC) Materials Research are Power Utility Companies, UK Industry in high added value manufacture and European households provided with low cost combined heat and power in an expanding $38b* worldwide solar market (*SolarBuzz website 2011). Highly efficient absorber materials coupled with large Negative Electron Affinity [NEA] diamond surfaces have the potential to provide economic, grid parity solar power. The project objectives and deliverables also have wide and varied applications in science and manufacturing; e.g. low noise electron emission and amplification, miniature high performance dynodes and electronic displays.

We have secured a number of interested industrial beneficiaries for the project that bring in kind value to the project. as project partner Magnox Ltd, has agreed to provide expert representation on the project steering committee in addition to the provision of operational data and sample graphite material. We attribute an in-kind value of £65,600 for their involvment, which covers 7 full man days at £800 per day (standard industry rate) and a value of £60,000 for provision of sample materials and data (including paperwork and shipment costs). Other associated stakeholders agreeing to provide steering input are the Nuclear Decommissioning Authority (NDA) and SEA Ltd, a leading international systems and engineering house for development of space nuclear power. The latter have significant links with the European Space Agency (ESA) and bring significant added value with regards to identifying and cultivating commercial opportunities for our arising technology.
We will maximise the impact of our technology by partnering with key strategic stakeholders (Magnox, NDA and SEA Ltd) to capitalise on expertise available from industry whilst also cultivating opportunities for commercialisation and follow-on funding.
The business opportunity is multifaceted:
- A long l, scalable nuclear battery technology using beta-emitting graphite waste to power a TDC
- Solar thermal power generation, utility scale >100MW with distributed solar dish concentrators with EON driving the device requirements at the early development stage
- High added value, UK manufacture of BTDC devices and complete power systems, potential system integrator for maximum exploitation in solar thermal microgeneration
- Low cost licensing of BTDC to Lower Economic Developed Countries with potential to yield carbon reduction benefits many times that which the same investment could yield in the Europe; with low cost, locally manufactured thermionic renewable energy replacing diesel generators
To maximise impact in the solar market an important technology goal is to differentiate the TDC from the many competing solar pow

Publications

10 25 50
 
Description Beta radiation is an effective secondary source of radiation for enhancing the processes involved in converting heat incident on a diamond electrode into thermionic electron emission and subsequent electrical power generation. The enhancement process requires the diamond to be functionalised with an elemental moiety to induce a surface dipole producing a near surface depletion region that can split electron hole pairs generated by the incident beta radiation and produce subsequently enhancement in the thermionic electron emission. This result is applicable to diamond voltaic devices, beta and gamma voltaics, as well as thermionic energy converters.
Patent has been filed on oxygen-lithium terminations on diamond for thermionic energy converters.
Exploitation Route Renewtec Dubai sponsored a PhD student (2017-2021) to continue diamond thermionic studies using the Bristol NanoESCA facility, CASTEP modelling using BlueCrystal and diamond growth facilities in the School of Chemistry.
University spin-out commercialising diamond batteries will also be developing beta-enhanced thermionic energy converters for terrestrial and space applications.
Sectors Aerospace, Defence and Marine,Electronics,Energy,Security and Diplomacy

 
Description Temperature stable secondary electron yield of lithiated diamond powders have been evaluated in photomultiplier tubes produced by ET Enterprises for potential use in demanding applications. Work on annealing studies of boron doped thin film diamond and intrinsic thin film diamond materials has been used to establish a university startup developing thermal management solutions for silicon-based electronics. Beta enhanced diamond electron emission results employing functionalised diamond surfaces, have shaped the work conducted under the follow-on EPSRC-funded project ASPIRE which is researching self-powered radiation sensors using diamond voltaics, and a spin-out company seeking to commercialise diamond batteries and thermionic energy converters.
First Year Of Impact 2019
Sector Electronics,Energy
Impact Types Economic

 
Description ARM power on a chip applications 
Organisation ARM Holdings
Country United Kingdom 
Sector Private 
PI Contribution Advising ARM on the value and opportunity of adopting our diamond beta-voltaics onto their processor chips, providing direct and constant power (albeit a very low current feed). ARM have identified a significant opportunity in the IoT field for our technology.
Collaborator Contribution The have attended Industrial Advisory Board meetings, made personal visits to discuss a potential project on growing diamond beta-voltaics directly onto their chip sets. We have also had support from ARM to select a sensory module from Texas Instruments and Low power Bluetooth transmitter incorporating ARM technology.
Impact No significant outputs as yet.
Start Year 2017
 
Description AWE - Disruptive technologies collaboration 
Organisation Atomic Weapons Establishment
Country United Kingdom 
Sector Private 
PI Contribution We have been working with the AWE as collaborators providing them with intelligence about new sensor technologies arising from the grant. Specifically AWE have been engaging on the development of low power sensor pobs for monitoring temperature, humidity and radiation intensity.
Collaborator Contribution The have attended Industrial Advisory Board meetings, provided contacts within BEIS and established a side project on sensor developments for monitoring storage environments at the Aldermaston site. We have been advised that they will let us deploy our sensor units on the Aldermaston site as a significant demonstration of the technology. They have also provided access to their advanced SIMS capability to make quantification of Boron in the diamond films we've been making.
Impact This partnership has led to us developing a PCB version of our prototype sensor pod technology that will be purchased and deployed by the AWE as a prototype demonstration. The project has been inherently cross-disciplinary involving electronic engineers, device physicists and materials scientists.
Start Year 2017
 
Description Al Hamad/Renewtec collaboration on diamond thermionic energy converters 
Organisation Association of Train Operating Companies
Country United Kingdom 
Sector Learned Society 
PI Contribution Joint author/inventor of a patent disclosure based on know how arising from the research project.
Collaborator Contribution Joint author/inventor of a patent disclosure based on know how arising from the research project.
Impact Patent application filed March 2017. Industry funding of £140k for funding overseas PhD student to continue Beta-enhanced thermionic Diamond Energy Converter research.
Start Year 2016
 
Description ESA ARTES 2019 project 
Organisation European Space Agency
Department Harwell Centre
Country United Kingdom 
Sector Public 
PI Contribution Technical support to diamond battery for spacecraft application
Collaborator Contribution Project management and systems engineering
Impact Physics, Chemistry, Engineering
Start Year 2019
 
Description Kyoto University Research Reactor Institute (KURRI) 
Organisation Kyoto University Research Reactor Institute
Country Japan 
Sector Academic/University 
PI Contribution We have been working with KURRI as our project partners to utilise their test reactor and Co-60 irradiation facility in Osaka to (I) neutron activate C-13 diamond samples and (2) utilise the irradiator facility to test our gamma voltaic prototype devices. As part of this we have modelled neutron irradiations of our diamond wafers in their reactor core.
Collaborator Contribution The have attended Industrial Advisory Board meetings in person and by Skype. They have also provided access to their Co-60 irradiator and have already deployed one set of test samples in their reactor core for neutron irradiation. They have provided VERY substantial in-kind support by providing this unique access.
Impact Access to a test reactor! We don't have one in the UK so this is a very significant outcome. What is even more substantial is that we don't have to pay for access.
Start Year 2017
 
Description RWM Ltd 
Organisation Nuclear Decommissioning Authority NDA
Department Radioactive Waste Management
Country United Kingdom 
Sector Public 
PI Contribution Providing information on the ASPIRE project and designing prototype sensor pods which might be suitable for deployment in a geological disposal facility to provide ultra-long life monitoring capability.
Collaborator Contribution Attendance at Industrial Advisory Board meetings, introductions to the Nuclear Decommissioning Authority (NDA) and advice on graphite fission wastes that might be of potential value to the ASPIRE project. Another significant contribution has been RWM getting the ASPIRE academics involved as partners on the IAEA working group on graphite nuclear wastes (GRAPA). The group meets every 6 months in Vienna and have a keen interest in the ASPIRE technology.
Impact None as yet
Start Year 2017
 
Description Sellafield - link for diamond devices 
Organisation Sellafield Ltd
Country United Kingdom 
Sector Private 
PI Contribution Development of an ASPIRE sensor pod for demonstration deployment at the Sellafield site, ultimately targeted for deployment in a nuclear waste store. The ASPIRE sensors are being designed specifically (with input from Sellafield) for nuclear deployments in the extreme radiation environments of Intermediate and High-level nuclear waste stores.
Collaborator Contribution Sellafield have been instrumental in a number of ways: (1) Providing industrial support for a PhD student aimed at developing the gamma-voltaic aspect of the ASPIRE technology, (2) Direct negotiation with the Regulator (ONR) and BEIS on commercialisation and legislation of the technology, (3) Attendance at Industrial Advisory Board meetings, (4) Advice on graphite wastes from fission power that might be most suitable for processing to recover C-14 for the ASPIRE beta-voltaics and (5) Developing opportunities for on-site demonstration deployments of the ASPIRE prototype sensor pods before the end of the project.
Impact This collaboration is inherently multi-disciplinary - involving materials scientists, electrical engineers and physicists. Already an outcome is that we have facilitated Sellafield being directly involved with the shaping of the Culham H3AT facility. Further significant outputs are planned once further patents are filed.
Start Year 2017
 
Description UKAEA Culham Centre for Fusion Energy 
Organisation Culham Centre for Fusion Energy
Country United Kingdom 
Sector Academic/University 
PI Contribution This is quickly establishing as a very significant new partnership, based around the beta and gamma voltaic devices made by my team in Bristol. We have conducted a significant body of neutronics modelling to calculate neutron activation of C-13 diamond and have made, for the first time, a C-13 diamond film created using closed loop CVD diamond growth (another first). Pure C-12 or C-13 diamond has a substantially higher thermal conductivity than normal/natural diamond and may provide an ideal coating materials for sensors or wall-bricks used inside existing and future fusion reactors.
Collaborator Contribution CCFE have funded a PhD at Bristol (matched with EPSRC DTA funding) starting in summer 2018. Bristol has matched this with a further studentship on isotopic diamond for plasma facing material coatings. CCFE have also helped us with access to the Materials Research Facility and have helped us identify a new route for creating diamond beta voltaic devices using tritium as the beta power source. Finally and most substantially they have sought and gained funding (~£35M) for the establishment of the H3AT facility for the processing and recovery of tritium and C-14 from irradiated reactor core graphite. We have been involved in the scoping of H3AT and continue to be involved as key stakeholders to ensure that the capability of the H3AT facility is suitable for providing an isotopic feedstock for the commercial production of our beta-voltaic devices.
Impact As stated above the funded studentship and the H3AT facility are very substantial outputs.
Start Year 2017
 
Title Diamond-based beta and gamma voltaic micro-power devices 
Description As per United Kingdom Patent Application No. 1707486.5, this patent was simultaneously filed in the US. 
IP Reference US Provisional Patent Application No. 62/504,012 
Protection Patent application published
Year Protection Granted 2017
Licensed No
Impact None as yet - we've tried to keep this technology commercially quiet due to further filings in process.
 
Title Diamond-based gamma and beta voltaic energy devices 
Description A process for the production of small low current atomic power cells made from diamond wafers. For the gamma voltaic the power is generated by harvesting an incident gamma flux and for the beta voltaic the device is impregnated with a beta emitting isotope (tritium, C-14 or Be-10). 
IP Reference GB1707486.5 
Protection Patent application published
Year Protection Granted 2017
Licensed No
Impact None as yet apart from weekly approaches from companies for this technology
 
Company Name Advanced DiamondX Ltd 
Description Advanced DiamondX is an innovative company specialising in Chemical Vapour Deposition (CVD) growth of diamond for industrial and research applications of thermal heat spreaders. The goal is to commercialise a number proprietary processes and equipment for making a range of thermally and/or electrically conductive diamond thin films or freestanding wafers for thermal management applications. The startup was established by Dr Xian Zhang, currently a QTEC Fellow at the University of Bristol. Bristol academics Dr Neil Fox and Dr James Smith from the Bristol Diamond laboratory are co-founders. The R&D labs od Avanced DiamondX are located at UnitDX in Bristol. 
Year Established 2018 
Impact Company only incorporated in January 2018. Currently in negotiation with Taiwanese PCB manufacturers to form a joint venture company.
 
Description #Diamond Battery activity 
Form Of Engagement Activity Engagement focused website, blog or social media channel
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact A public engagement campaign which has reached over 12 million people. Initially launched as a concept at the Cabot annual innovation lecture by Prof Tom Scott, the programme of public outreach around the diamond battery has sold the concept of recycling valuable isotopes from nuclear waste to make micro-power cells with a 5000 half life. As a major activity we made an animated video and posted it on the internet. It went viral and attracted millions of views world wide. This led to dozens of media (TV, Radio, internet) interviews and news stories across the world. It also led to VERY substantial industrial interest which continued even today.
Year(s) Of Engagement Activity 2017,2018
URL http://www.bristol.ac.uk/news/2016/november/diamond-power.html
 
Description 'The Next Curie' collaboration with The Belgian Nuclear Forum. 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact This was an outreach collaboration with the Belgian Nuclear Forum, the professional association of Belgian nuclear companies. They have an annual campaign for promotion of nuclear science and technology with a focus on start-ups and innovation. Their aim is to show to the Belgian public that nuclear is a dynamic technology with several innovative projects ongoing.

Our ASPIRE project was selected as an inspirational and innovative idea to present to the public via a large media campaign (related to the 150th anniversary of Marie Curie). They produced a news story and dissemination article which was shared as part of the event and surrounding promotion in the media.
Year(s) Of Engagement Activity 2017
 
Description Bristol public lecture 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Public/other audiences
Results and Impact 40 people attended a public lecture organised by the Bristol Centre for Nano Science and Quantum Information to showcase the research on diamond materials for renewable energy applications.
Year(s) Of Engagement Activity 2015
 
Description Invited talk EMRS 2015 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact European Materials Research Society Fall Meeting. Talk was delivered in Nanomaterials for energy session .
Year(s) Of Engagement Activity 2015
URL http://www.european-mrs.com/2015-fall-symposium-d-european-materials-research-society
 
Description NASA Workshop on Thermionic Energy Conversion 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Industry/Business
Results and Impact Organised by Dr Jeff George programme manager at NASA Johnson. Attendees were NASA project scientists and researchers working in the area of thermionic energy conversion. The workshop aimed bring together leading academic research groups to build a technology roadmap for future development of energy converters for manned space exploration as well as terrestrial application.
Year(s) Of Engagement Activity 2014
URL http://www3.nd.edu/~dgo/NASA.html