Composition-dependent electrochemical activity of Ag-based alloy nanotubes for efficient nitrogen reduction under ambient conditions

The composition-activity relationship is highly desirable for electrocatalytic nitrogen reduction reaction (NRR) because it could guide the rational design of efficient NRR catalysts. In this work, the composition effect of Ag-based alloy nanotubes on electrocatalytic NRR activity is systematically investigated. It is found that, among AgAu nanotubes with atomic ratio from 8:1 to 1:2, Ag 2 Au 1 alloy nanotubes achieve the largest enhancement for NRR catalytic activity. Specifically, the NH 3 production rate and faradaic efficiency of Ag 2 Au 1 nanotubes are 21.7 μg h −1 mg cat −1 and 3.8% at −0.30 V vs. RHE, respectively, which were 3.0 and 3.6 times higher than those of Ag nanowires . Compared with Ag 2 Pd 1 and Ag 2 Pt 1 nanotubes, Ag 2 Au 1 hollow nanotubes also exhibit a better NRR catalytic activity. Theoretical calculation results indicate that the negative ion characteristic of Au atoms in the Ag 2 Au 1 alloy is favorable for the adsorption and activation of N 2 . Moreover, Ag 2 Au 1 nanotubes showed stable NH 3 yield rate and faradaic efficiency up to 18 h, revealing its great potential for promising NRR electrocatalysis .