Colloidal Synthesis of Cu 3 N Nanorods and Construction of Cu 3 N-Cu 2 O Heteronanostructures via Epitaxial Growth.

The synthesis of transition metal nitrides nanocrystals (TMNs NCs) has posed a significant challenge due to the limited reactivity of nitrogen sources at lower temperatures and the scarcity of available synthesis methods. In this study, we present a novel colloidal synthesis strategy for the fabrication of Cu 3 N nanorods (NRs). It is found that the trace oxygen (O 2 ) plays an important role in the synthesis process. And a new mechanism for the formation of Cu 3 N is proposed. Subsequently, by employing secondary lateral epitaxial growth, the Cu 3 N-Cu 2 O heteronanostructures (HNs) can be prepared. The Cu 3 N NRs and Cu 3 N-Cu 2 O HNs were evaluated as precursor electrocatalysts for the CO 2 reduction reaction (CO 2 RR). The Cu 3 N-Cu 2 O HNs demonstrate remarkable selectivity and stability with ethylene (C 2 H 4 ) Faradaic efficiency (FE) up to 55.3%, surpassing that of Cu 3 N NRs. This study provides innovative insights into the reaction mechanism of colloidal synthesis of TMNs NCs and presents alternative options for designing cost-effective electrocatalysts to achieve carbon neutrality.