High capacity mixed metal borohydrides ammoniates for hydrogen energy storage applications

Hydrogen is a promising alternative energy carrier for the future due to its high specific energy and environmental friendliness. The development of hydrogen storage technologies to support renewable energy systems and low-carbon transportation is important. Currently, high pressure compressed hydrogen gas (700 bar) is used for vehicles, however they are very costly and achieve low energy densities. Many light weight hydrides, such as LiBH4 and LiAlH4, although having high storage capacities have major drawbacks of irreversibility and high working temperatures. Ammonia can be catalytically split in to N2 and H2 and its hydrogen content is about 17.3 wt.%, which can store 30 % more energy per volume than liquid H2. Utilization of NH3 for on-board storage system is hampered due to its toxicity. In recent years, a new class of materials called Metal Borohydride Ammoniates (MBAs) show improved hydrogen storage properties. MBAs tend to release hydrogen/ammonia gas at more practical temperatures and with greater purity. This research will focus on the development of novel Mixed Metal Borohydride Ammoniates (MMBAs) to achieve even higher hydrogen storage densities, elucidate the reaction mechanisms responsible for the decomposition process and investigate catalysts to accelerate the release of hydrogen from these materials. The project involves synthesis of various MMBAs, a variety of material characterisation techniques (e.g. XRD, TGA, DSC, FTIR, GC-MS) and hydrogen performance testing by the Sieverts' technique. There will also be opportunities to use large scale facilities such as neutron diffraction experiments at Institut Laue Langevin in France.

The RI self-assessment of an individual's research projects will mean that the cohort have a high degree of understanding of the potential beneficial impact from their research on the economy, society and the environment. This then places the cohort as the best ambassadors for the CDT, hence most pathways to impact are through the students, facilitated by the CDT.

Industrial impact of this CDT is in working closely together with key industry players across the hydrogen sector, including through co-supervision, mentoring of doctoral students and industry involvement in CDT events. Our industrial stakeholders include those working on hydrogen production (ITM Power, Hydrogen Green Power, Pure Energy) and distribution (Northern Gas, Cadent), storage (Luxfer, Haydale, Far UK), safety (HSL, Shell, ITM Power), low carbon transport (Ulemco, Arcola Energy), heat and power (Bosch, Northern Gas).

Policy impact of the CDT research and other activities will occur through cohort interactions with local authorities (Nottingham City Council) and LEPs (LLEP, D2N2) through the CDT workshops and conference. A CDT in Parliament day will be facilitated by UKHFCA (who have experience in lobbying the government on behalf of their members) and enable the cohort to visit the Parliamentary Office for Science and Technology (POST), BEIS and to meet with local MPs. Through understanding the importance of evidence gathering by Government Departments and the role this has in informing policy, the cohort will be encouraged to take the initiative in submitting evidence to any relevant requests for evidence from POST.

Public impact will be achieved through developing knowledge-supported interest of public in renewable energy in particular the role of hydrogen systems and infrastructure. Special attention will be paid to demonstration of safety solutions to prove that hydrogen is not more or less dangerous compared to other fuels when it is dealt with professionally and systems are engineered properly. The public, who are ultimate beneficiaries of hydrogen technologies, will be engaged through different communication channels and the CDT activities to be aware of our work. We will communicate important conclusions of the CDT research at regional, national, and international events as appropriate.

Socio-economic impact. There are significant socio-economic opportunities, including employment, for hydrogen technologies as the UK moves to low carbon transport, heat and power supply. For the UK to have the opportunity to take an international lead in hydrogen sector we need future innovation leaders. The CDT supported by partners we will create conditions for and exploit the opportunities to maximise socio-economic impact.

Students will be expected in years 3 and 4 to undertake a research visit to an industry partner and/or to undertake a knowledge transfer secondment. It is expected these visits (supported by the CDT) will be a significant benefit to the student's research project through access to industry expertise, exploring the potential impact of their research and will also be a valuable networking experience.