Tunable C<sub>2</sub> selectivity in CO electroreduction via charge-asymmetric dual-metal catalysts on ferroelectric In<sub>2</sub>Se<sub>3</sub>

The development of efficient catalysts for the electrocatalytic CO reduction reaction toward high-value C2 products is critical for addressing pressing energy and environmental challenges. Dual-metal catalysts have emerged as promising candidates due to their potential to facilitate C−C coupling, a key step in C2 product formation. However, their activity and selectivity are highly dependent on the charge states of the active sites. Modulating asymmetric charge distribution between metal centers offers a viable strategy to enhance C−C coupling efficiency and product selectivity. In this study, we employ density functional theory to investigate heteronuclear dual-atom catalysts (DACs) anchored on ferroelectric In2Se3 and impact of polarization on charge states of metal sites. We find that Pd−Nb and Rh−Nb DACs form spatially separated charge centers with opposite signs, which significantly reduce the energy barrier for C−C coupling compared to homonuclear Nb−Nb DACs, enabling thermodynamically favorable C−C bond formation. The Coulomb interaction between oppositely charged centers is identified as a key descriptor governing C−C coupling efficiency. Furthermore, ferroelectric polarization switching of In2Se3 offers dynamic modulation of reaction pathways and product selectivity. Pd−Nb@In2Se3 under downward polarization (P↓) favors ethane formation with a limiting potential of −1.06 eV, whereas upward polarization (P↑) shifts the reaction toward an alternative C−C coupling pathway with a higher overpotential (−1.47 eV). Similarly, Rh−Nb@In2Se3 selectively produces ethanol under P↓, but methane under P↑. Importantly, both Pd−Nb and Rh−Nb DACs exhibit stronger CO adsorption than H adsorption, favoring CORR over the competing hydrogen evolution reaction. These findings underscore the potential of ferroelectric DACs as tunable and selective catalysts for CORR, offering a compelling strategy for the rational design of next-generation electrocatalysts for decarbonization.