Effects of A-Site Alkaline Earth Doping on CO ₂ Adsorption and Electrical Conductivity in La ₂ CuO ₄

The electrocatalytic carbon dioxide reduction reaction (eCO 2 RR) represents a promising approach for converting CO 2 into value-added chemicals and fuels. We focus on the doping modification of La 2 CuO 4 to enhance CO 2 adsorption efficiency and improve electrical conductivity. To address the challenge of activating CO 2 adsorption, alkaline-earth metals (Ca, Sr, and Ba) doped La 2 CuO 4 catalysts were designed and synthesized. Comprehensive characterization was performed to examine their phase structures, morphologies, surface elemental states, electrical conductivities. CO 2 adsorption and contact angle measurements were also carried out, considering that eCO 2 RR takes place at a gas–liquid–solid three-phase interface. Compared to conventional La 2 CuO 4 doped with rare-earth metals at the A-site, the introduction of alkaline-earth metals not only improves the CO 2 chemisorption capacity but also enhances the electron conductivity of the catalysts, thereby intrinsically boosting the eCO 2 RR activity.