The TROPHY project aims to develop highly selective and sensitive optical and chemirestitive hydrogen sensors using environmentally friendly and cost-effective processes. These advancements will support the growth of the hydrogen economy by addressing current limitations in sensor detection, response times, recovery times, and selectivity. The project will employ aerosol-based methods (e.g. spark ablation) to prepare Pd-based nanoparticulate thin films, including pure, alloyed, decorated, and core-shell structures, and will evaluate their sensing performance.