Development of innovative technologies for direct seawater electrolysis

The expectations stemming from the aforementioned expected outcomes create a set of challenges to be overcome in order to produce electrolysers of various scale of power for distributed hydrogen production, performed without other than basic mechanical filtration or purification of seawater. In order to understand and tune reaction mechanisms describing the desired catalytic activities and the overall stability and selectivity, special attention needs to be paid to in-depth experimental, computational and theoretical insight into the mechanistic pathways and properties of the electrode-electrolyte interface under operating conditions. The major effort should, therefore, focus on one hand on the improvement of the hydrogen electrode to work in this harsh environment and on the other hand on the improvement of the selectivity towards the oxygen evolution at the anode electrode, as well as, to the durability issues stemming from both corrosion processes and catalyst (and membrane when applies) poisoning.

The project should consider the following requirements:

• Identify and develop suitable materials (catalysts, membrane when implemented, coatings, Porous Transport Layers, Bipolar Plates, sealings), as well as electrolyser design options and operating conditions relevant to the seawater composition of interest in correlation with electrolyser cell performance and selectivity.
• Experimental and model-based studies on the durability of materials, components and resulting prototype in harsh environment.
• Optimise advanced cost effective and limited CRM use electrocatalysts concerning activity, durability, and selectivity for the HER and OER with high tolerance to poisoning caused by chlorides, salts, and various contaminants (including ammonia and organic contaminants) present in seawater.
• Reduce the experimental efforts by means of the application of computer modelling tools including computational material science-based simulation approach.
• Integrate and test corrosion resistant new cost effective and available components into a prototype short stack (> 5cells) operated under dynamic mode simulating the intermittent behaviour of solar or wind power sources (RES).
• Identify the correlations between the durability of the component/system under development and its cyclic operating conditions.
• Operate the stack under representative conditions (to evaluate its performance and durability for at least 2000 h of cumulative operation and a minimum of 1500 cycles from idle to nominal operating conditions to simulate the dynamic electricity input from fluctuating renewable sources). The degradation rates should be measured during this time and reported in %/1000 h.
• Identify, define, and test a safe operating window in terms of durability based on the typical characteristics (e.g. salinities) of at least two types of sea feedwater corresponding to the prospective areas of application – relevant synthetic seawater according to the above identified geographic regions can be considered at some stages of long-term testing while final tests should consider the use of the natural water samples.
• Assess the circularity and techno-economic and environmental feasibility of the proposed technology, including the CRM cost – system durability tradeoff and evaluation of the brine as a source of extractable raw materials.

Consortia are encouraged to explore synergies with relevant ongoing projects funded by the European Innovation Council (EIC) Pathfinder Challenge 2021EIC Pathfinder Challenges 2021 (HORIZON-EIC-2021-PATHFINDERCHALLENGES-01), as relevant.

Proposals are encouraged to explore synergies with projects within the metrology research programme run under the EURAMET research programmes EMPIR and EMRP (in particular on metrology for standardised seawater pHT measurements and metrology for ocean salinity and acidity.

Activities related to test protocols and procedures for the performance and durability assessment of water electrolysers fed with low grade water should foresee a collaboration with JRC (see section 2.2.4.3 "Collaboration with JRC"), in order to support EU-wide harmonisation. Test activities should adopt the already published EU harmonised testing protocols to benchmark performance and quantify progress at programme level.

For additional elements applicable to all topics please refer to section 2.2.3.2.

Activities are expected to start at TRL 2 and achieve TRL 4 by the end of the project - see General Annex B.

The JU estimates that an EU contribution of maximum EUR 4.00 million would allow these outcomes to be addressed appropriately.

The conditions related to this topic are provided in the chapter 2.2.3.2 of the Clean Hydrogen JU 2024 Annual Work Plan and in the General Annexes to the Horizon Europe Work Programme 2023–2024 which apply mutatis mutandis.