Elucidating the Role of Ru-Ov-Ce Interfacial Structure on Ru/Silicate-1 Catalyst by the Doping of CeO2 for Ammonia Decomposition.

Interface engineer of Ru-based catalysts has become an attractive strategy to improve ammonia (NH3) decomposition performance by precisely modulating the microenvironment of Ru site. Therefore, the Ru-Ov-Ce interfacial structure is constructed on Silicate-1 (S-1) to improve the NH3 decomposition performance of Ru/S-1 catalyst. The activity test suggests that the generation of Ru-Ov-Ce interfacial structure considerably improved the catalytic performance of Ru/S-1 catalyst, boosting the specific activity from 2546.7 to 4461.3 h-1 at 450 °C, and displays promising cycle and long-term stability. Comprehensive characterization results reveal that Ru-Ov-Ce interfacial structure is favorable for enhancing metal-support interaction, inducing the generation of oxygen vacancies, and optimizing the electronic structure of Ru species. Moreover, Ru-Ov-Ce interfacial structure exhibits favorable adsorption performance for NH3 and induces the generation of medium-strong basic sites, which contributed to N2 desorption. Furthermore, the in situ DRIFTS and DFT calculations reveal that Ru-Ov-Ce interfacial structure performed superbly in the cleavage of N-H bonds and N* and H* recombination, which greatly lowers the reaction energy barriers and improves the reaction kinetics. This work thoroughly explores the specific action mechanisms of superior Ru-Ov-Ce interfacial structure in NH3 decomposition, offering a valuable reference for the construction of highly active interface on Ru-based catalysts.