Cascade NH(3) Oxidation and N(2)O Decomposition via Bifunctional Co and Cu Catalysts

[Image: see text] The selective catalytic oxidation of NH(3) (NH(3)–SCO) to N(2) is an important reaction for the treatment of diesel engine exhaust. Co(3)O(4) has the highest activity among non-noble metals but suffers from N(2)O release. Such N(2)O emissions have recently been regulated due to having a 300× higher greenhouse gas effect than CO(2). Here, we design CuO-supported Co(3)O(4) as a cascade catalyst for the selective oxidation of NH(3) to N(2). The NH(3)–SCO reaction on CuO–Co(3)O(4) follows a de-N(2)O pathway. Co(3)O(4) activates gaseous oxygen to form N(2)O. The high redox property of the CuO–Co(3)O(4) interface promotes the breaking of the N–O bond in N(2)O to form N(2). The addition of CuO–Co(3)O(4) to the Pt–Al(2)O(3) catalyst reduces the full NH(3) conversion temperature by 50 K and improves the N(2) selectivity by 20%. These findings provide a promising strategy for reducing N(2)O emissions and will contribute to the rational design and development of non-noble metal catalysts.