General synthesis and atomic arrangement identification of ordered Bi-Pd intermetallics with tunable electrocatalytic CO 2 reduction selectivity.

Intermetallic compounds (IMCs) with fixed chemical composition and ordered crystallographic arrangement are highly desirable platforms for elucidating the precise correlation between structures and performances in catalysis. However, diffusing a metal atom into a lattice of another metal to form a controllably regular metal occupancy remains a huge challenge. Herein, we develop a general and tractable solvothermal method to synthesize the Bi-Pd IMCs family, including Bi 2 Pd, BiPd, Bi 3 Pd 5 , Bi 2 Pd 5 , Bi 3 Pd 8 and BiPd 3 . By employing electrocatalytic CO 2 reduction as a model reaction, we deeply elucidated the interplay between Bi-Pd IMCs and key intermediates. Specific surface atomic arrangements endow Bi-Pd IMCs different relative surface binding affinities and adsorption configuration for *OCHO, *COOH and *H intermediate, thus exhibiting substantially selective generation of formate (Bi 2 Pd), CO (BiPd 3 ) and H 2 (Bi 2 Pd 5 ). This work provides a comprehensive understanding of the specific structure-performance correlation of IMCs, which serves as a valuable paradigm for precisely modulating catalyst material structures.