Constructing heterogeneous asymmetric sites for highly-selective methane production from CO₂ electroreduction

We have engineered heterogeneous asymmetric sites at the Eu₂O₃/CuO interface to enhance the methane formation pathway during CO₂ electroreduction, where Cu²⁺ species can stabilize the crucial *CO intermediate, whereas Eu³⁺ sites facilitate the hydrogenation of *CO by supplying more reactive *H species. Consequently, the Eu₂O₃/CuO heterostructure attains a remarkable faradaic efficiency of up to 63.1% for methane production.