Uncovering the Structure of Heterogeneous Catalysts Using Atomic Pair Distribution Function Analysis

Abstract

Heterogeneous catalysts are complex materials, often containing multiple atomic species and phases with various degrees of structural order. The identification of structure – performance relationships that rely on the availability of advanced structural characterization tools, is key for a rational catalyst design. Structural descriptors in catalysts can be defined over different length scales from several Å up to several nanometers (crystalline structure), requiring structural characterization techniques covering these different length scales. Pair distribution function (PDF) analysis is a powerful method to extract structural information spanning from the atomic to the nanoscale under in situ or operando conditions. We discuss recent advances using PDF to provide insight into the atomic-to-nanoscale structure of heterogeneous catalysts.