Electrochemical Potential-Driven Evolution of *CO Electronic Structure and Adsorption Configuration on Te-Based Diatomic Catalysts for Enhanced CO₂ Reduction

Abstract

The recent experimental synthesis of novel α-Te, which exhibits excellent stability and outstanding electronic transport properties, makes it a promising candidate for the CO2 reduction reaction (CO2RR). Based on density functional theory (DFT), 21 diatomic catalysts (M1M2@Te) were constructed by embedding paired transition metal atoms. Through combined screening based on CO2RR selectivity and the limiting potential (UL) metric, three highly promising catalysts were successfully identified: CoNi@Te, FeNi@Te, and FeCu@Te, with UL values of -0.64 V, -0.77 V, and -0.21 V respectively. By studying their UL under different applied potentials, it was found that the electrocatalytic performance exhibits significant potential dependence. At -0.4 V, the limiting step of FeCu@Te shifts due to weakened *CO adsorption, driven by frontier orbital realignment at Fe, Cu active sites. These results demonstrate that the electrode potential effectively tunes the electronic structure of the diatomic active sites and their *CO adsorption strength. This potential responsive behavior provides important theoretical guidance for understanding the activity of diatomic catalysts under realistic operating potentials. The constant potential calculation corrected the calculations for the neutral charge state, making the calculations more in line with the working conditions. This work provides important insights into Te-doped diatomic electrocatalysts for CO2RR and offers a theoretical foundation for developing efficient electrocatalysts in the future.