Lattice distortion induced electronic coupling results in exceptional enhancement in the activity of bimetallic PtMn nanocatalysts

Lattice strain plays a critical role in structural heterogeneity and surface electronic properties of bimetallic nanocatalysts. However, understanding of how to engineer optimal electron transfer in anisotropic bimetallic crystal's remains a grand challenge to achieve enhanced catalytic performances. We investigate beyond conventional polymer based core-shell and alloy structures, and present unique lattice distorted PtMn catalysts fabricated via a cooperative self-assembly method. The strong internal strain between Pt and Mn lattices is found to induce the structural distortion of anisotropic PtMn crystals and formation of asymmetric flower shapes, leading to stretched Pt and contracted Mn lattices. Such distorted bimetallic crystals exhibit unusual electronic coupling and an eight-fold synergistic enhancement in catalytic oxidation of renewable biomass feedstocks compared with monometallic Pt catalysts. The novel synthesis technique and revealed electronic coupling mechanism described herein opens the door for the rational discovery of other bimetallic nanocatalysts with positive synergy. (C) 2017 Elsevier B.V. All rights reserved.