Rational design of 2D ferroelectric heterogeneous catalysts for controllable hydrogen evolution reaction

Abstract

Understanding the decisive factors of electrochemical reactions and developing effective manipulation strategies are crucial for the rational design of highly active catalysts and renewable energy conversion technologies. In this work, with a transition metal embedded in nitrogen-doped graphene (TMN₃) as the example, it is found that the electron doping and band shift are the dominant factors for HER activity by using first-principles calculations, indicating the possibilities to design the optimal catalysts by the manipulations of electron transfer and band states near the Fermi level. Here, a novel approach to achieve hydrogen evolution reaction (HER) control via ferroelectric (FE) switching is proposed. Our theoretical results reveal that the electrocatalytic HER performance of TMN₃ catalysts can be well controlled when they are placed on the surface of FE In₂Se₃, in which CoN₃/P↓–In₂Se₃ exhibits the best HER performance with a Gibbs free energy change of −0.044 eV. The adsorption energies and electron transfer can be effectively modulated when the polarization is reversed, due to the polarization induced electron redistribution, magnetic moment changes, and band state shifts near the Fermi level. The FE-controlled HER activity is further supported by the catalyst-electronic-magnetic relationship under the electric field. This systematic study provides a fundamental understanding for new insights into the design and application of cost-effective 2D ferroelectric heterostructure catalysts.