Tunable N₂ fixation enabled by ferroelectric switching in doped graphene/In₂Se₃ dual-atom catalysts

Abstract

The electrochemical nitrogen reduction reaction (NRR) provides a sustainable alternative to ammonia synthesis. However, the development of catalysts with high activity and selectivity under ambient conditions remains a significant challenge. In this work, we propose a class of dual-atom catalysts (DACs), consisting of two metal atoms embedded in nitrogen-doped porous graphene (M₂NPG) supported on a ferroelectric α-In₂Se₃ monolayer. Using density functional theory (DFT) calculations, we explore the effect of ferroelectric polarization switching on the structural stability, catalytic performance, and reaction mechanisms of these DACs. By computationally screening 27 metal atoms as active sites, we identify four promising candidates (V, Co, Ru, and Ta) with V₂NPG@In₂Se₃ standing out due to its exceptional properties. The precise control of NRR pathways, along with tunable limiting potentials and selective product formation, can be achieved through the polarization switching of the α-In₂Se₃ monolayer. The combination of low limiting potential, abundant active sites, tunable catalytic behavior, and high selectivity against the hydrogen evolution reaction (HER) highlights the potential of V₂NPG@In₂Se₃ as a promising alternative to traditional single-atom catalysts. This work demonstrates a versatile strategy for integrating DACs with ferroelectric materials, offering valuable insights into designing next-generation catalysts for NRR and beyond.