Ni-MOF-74 Derived Carbon-Based Ni Catalysts for Efficient Catalytic Ammonia Synthesis via Pulsed DBD Plasma

Designing efficient noble metal-free catalysts for plasma-catalytic ammonia synthesis is significant and challenging. Carbon-based metal catalysts were prepared at different pyrolysis temperatures using the Ni-MOF-74 precursor. The effects of Ni-MOF-74 and its derived carbon-based metal catalysts on pulsed dielectric barrier discharge (DBD) plasma ammonia synthesis were investigated. The results showed that Ni-MOF-74-300 with both the MOF structure and nickel metal particles exhibited the best catalytic performance for ammonia synthesis. The ammonia synthesis rate reached 41.38 mmol g −1 h −1 , whereas the nitrogen conversion rate was as high as 1.54% with an energy yield of 3.04 g kWh −1 . Compared to the situation of plasma only, the ammonia synthesis rate, nitrogen conversion rate, and energy yield were increased by 28.46 times, 5.7 times, and 5.5 times, respectively.