Recently, a team led by Prof. LU Junling collaborating with Prof. LI Weixue's and Prof. WEI Shiqiang's team, revealed the conjugated dual size effect of core-shell bimetallic nanocatalysts for the first time, with the activity of the catalysts increases with the core size in the benzyl alcohol oxidation reaction. Their work was published in Nature Communications.
Bimetallic catalysts are widely used in different chemical synthesis for their bimetallic synergy varying with compositions and structures. Compared to alloy catalysts, the peculiar lattice strains and ligand effects of core-shell catalysts can optimize the geometric and electronic properties. The shell thickness significantly affects bimetallic synergy because the ligand effects and the charge transfers between components usually happen at the core-shell interface.
The lattice strains in core-shell catalyst occur due to lattice mismatch between the metal core and the shell, which have a prominent effect on the electronic structure of the metal shell and the overall activity of catalysts. When the core size is reduced, its lattice contracts considerably, which affects its mismatch with shell lattice, consequently modulates the lattice strains in the shell. This dual size effect of core-shell particles has not yet been explored due to the immense challenge in adjusting the core size and shell thickness at atomic level.
