Synergistic CO ₂ ‐Philic/H ₂ O‐Phobic Interface Engineering in PEDOT/NHCS/Au Composite for High‐Efficiency CO ₂ Electroreduction With Suppressed Hydrogen Evolution Reaction

ABSTRACT The electrocatalytic CO 2 reduction reaction (CO 2 RR) offers a viable solution for the conversion and storage of renewable energy. Utilizing electronic metal‐support interactions (EMSI) to adjust the electronic properties of metal catalysts has demonstrated effectiveness in enabling highly selective CO 2 electroreduction. Here, a cleverly designed ternary composite is presented, which is synthesized by using nitrogen‐doped hollow carbon spheres (NHCS) as the substrate and coating them with poly(3,4‐ethylenedioxythiophene) (PEDOT) to form a PEDOT/NHCS support for anchoring Au nanoparticles. This innovative design enables the catalyst to reach a stunning 98.21% at −0.8 V versus RHE, achieving an extraordinarily high Faradaic efficiency for CO (FE CO ) over a broad potential window (−0.6 to −1.5 V vs. RHE). The result is mainly due to the Au–S bond between the S in the PEDOT thiophene ring and the metal Au, which induces electron transfer, causing the d‐band center of the Au atoms to shift negatively. The hydrophobic surface of PEDOT and the hollow structure of NHCS synergistically construct an interface of “CO 2 ‐philic and H 2 O‐phobic.” This interface, in coordination with the Au NPs, enhances CO 2 adsorption, stabilizes the *COOH intermediate, accelerates the desorption of *CO, and simultaneously weakens the competitive adsorption of *H, effectively suppressing the HER.