Engineering direct 3d–4f orbital coupling by confining Cu–Ln pairs in paddlewheel metal–organic frameworks for efficient CO 2 electromethanation

Direct 3d–4f orbital coupling engineered by confining Cu–Er pairs in paddlewheel frameworks strengthens *CO adsorption and lowers the *CO → *CHO barrier, enabling efficient CO 2 electromethanation with 82% CH 4 faradaic efficiency.