Introducing La into a Customized Dual Cu Covalent Organic Framework to Steer CO 2 Electroreduction Selectivity from C 2 H 4 to CH 4

Customizing multi‐metal site catalysts for achieving controllable CO 2 reduction reaction (CO 2 RR) product tuning holds immense promise yet poses formidable challenges. The traditional synthesis method of multi‐metal sites is the pyrolysis of metal‐containing precursors, which is inherently uncontrollable. Herein, a bottom‐up strategy is employed to customize and synthesize multi‐metal sites in covalent organic frameworks (COFs), aiming to controllably switch the CO 2 reduction selectivity by regulating the electronic structure of active sites. Briefly, La element provides chances for manipulating and finetuning the electronic structure of the customized dual Cu sites, and converts the main catalytic product of CO 2 RR from ethylene to methane. Density functional theory calculations show that the introduction of La alters the electronic structure around Cu, enhances CO 2 and H 2 O activation, and changes the formation of energy barriers of key intermediates. To the best of the author's knowledge, this study constructed the first example of customized multi‐metal site COF catalysts and provided new ideas for controllable modulation of products.