Intermetallics in catalysis: An exciting subset of multimetallic catalysts

In this article, we highlight the growing application of intermetallic compounds in heterogeneous catalysis. We clearly discuss intermetallics as distinct from other multi-metallic systems (such as alloys, surface modifiers and dopants). Intermetallics possess a number of attributes over random alloys (i.e., solid solutions) and serve as model catalysts for a number of industrially relevant reactions. We review a variety of methods used for the synthesis of a large number of intermetallic compounds and discuss how standard material characterization techniques can be extended to intermetallics to gain important insight regarding active site morphology, a critical metric in heterogeneous catalyst design. We further summarize the use of intermetallics in understanding changes in reactivity and selectivity due to geometric and electronic effects, with emphasis on determining compositional and structural factors of the active site. We conclude with a brief summary of avenues for future advances in the field and its potential to contribute to environment and economy.