Activating nano-bulk interplays for sustainable ammonia electrosynthesis

Small changes in a catalyst's composition, modification, and/or integration into a reactor can have significant yet often poorly understood effects on (electro)catalysis. Here we demonstrate the careful tailoring of Ru/La0.25Ce0.75O2-x catalysts through the post-synthesized hydrothermal treatment together with control over the Ru loadings to create hydroxyl groups and electronic restructuring for ammonia electrosynthesis. When integrated into a protonic ceramic electrolyzer, the in situ formed Ce3+-OH/Ru sites facilitate both the N N decoupling and N-H formation at 400 degrees C and 1 bar of N-2, boosting the ammonia production rate (2.92 mol h(-1) m(-2)) up to 100-fold higher than the current state-of-the-art electrolyzers. Moreover, such catalysts and electrolyzer design concepts can be readily tuned to more complex applications such as coproducing ammonia and other chemicals with hydrocarbons as direct hydrogen sources. The creation of coordinated saturated support -OH/metal sites in the advanced electrolyzer offers an attractive approach for future clean-energy and green-chemical industries.

Automated summary

Small changes in catalyst composition and modification can greatly enhance (electro)catalysis. By carefully tailoring the Ru/La0.25Ce0.75O2-x catalysts through hydrothermal treatment and control over Ru loadings, the ammonia production rate can be increased significantly. The catalysts formed in a protonic ceramic electrolyzer facilitate ammonia synthesis and can be applied to more complex reactions.