Plasma spray coatings as catalysts for water splitting : exploring novel materials and strategies

Abstract: Today, fossil fuels still play a dominant role in the global energy systems. However, they are depleting quickly and the combustion of them causes many environmental concerns, including global warming, air pollution, ozone layer depletion, and acid rain. In response to these environmental challenges, a transition from fossil fuel energy sources towards sustainable alternatives is urgent and necessary. Unlike traditional fossil fuels, hydrogen serves as an environmentally friendly fuel with exceptional energy density, and its combustion generates no greenhouse gases. Moreover, hydrogen holds the versatility to be produced, stored, and utilized by various sectors, including transportation, industry, and electricity generation. Electrolyzer technology offers a sustainable pathway for clean hydrogen production when using electricity generated from renewable sources such as solar and wind power. The integration of hydrogen into energy systems holds significant potential for a decarbonized and sustainable future.In this thesis, we focused on creating affordable coatings using earth-abundant transition metals and explored their application as electrocatalysts for hydrogen and oxygen production in alkaline and acidic environments. We developed novel synthetic routes and new materials, we studied their intricate structure and composition, and we were able to fine-tune their catalytic activity and durability. Our findings demonstrated that plasma spray technology offers a scalable approach for producing highly active catalysts, while also developing coatings that can tolerate acidic environments and extend the lifetime of the state-of-the-art oxygen evolution catalysts. Furthermore, we tested and discussed alternative materials aiming to offer cost-effective substitutes for expensive Pt-based electrocatalysts for hydrogen production.