Oxygen vacancy-rich Fe2O3/Co3O4 heterostructure electrocatalyst promotes N2 activation for efficient nitrogen reduction

The adsorption and activation of N 2 as well as the competitive hydrogen evolution reaction (HER) pose significant challenges to the electrocatalytic nitrogen reduction reaction (ENRR), which severely limits its industrial application. Therefore, exploring the ENRR electrocatalysts with high activity and selectivity is an extremely important task. In this work, the oxygen vacancy-rich Fe 2 O 3 /Co 3 O 4 heterostructures (referred to as Vo-X-Fe 2 O 3 /Co 3 O 4 ) were rationally designed by employing Co 3 O 4 as a template via a simple hydrothermal and subsequent calcination method, which acted as highly efficient ENRR electrocatalysts. The electrocatalytic activity of Vo-X-Fe 2 O 3 /Co 3 O 4 can be easily regulated by optimization of the Fe content and the introduction of oxygen vacancy (Vo). The results demonstrate that the optimized Vo-1.0-Fe 2 O 3 /Co 3 O 4 catalyst achieves a high NH 3 yield of 47.37 μg h −1 mg cat −1 and a Faradaic efficiency (FE) of 22.42 %. Moreover, the excellent stability and reproducibility are also demonstrated. The comprehensive characterizations reveal that the exceptional performance of Vo-1.0-Fe 2 O 3 /Co 3 O 4 can be attributed to the improved N 2 adsorption and activation, restricted competitive HER and promoted electron transfer kinetics induced by the synergistic introduction of Vo and Fe. This work emerged a new speculating orientation for rational design of ENRR catalysts.