Redox coupling of metals drives rate enhancement in thermochemical oxidative dehydrogenation

Abstract

Abstract Supported bimetallic catalysts commonly exhibit higher rates of reaction compared to their monometallic counterparts, but the origin of these enhancements is often poorly defined. The recent discovery that cooperative redox enhancement effects in Au-Pd systems promote bimetallic catalysis in thermochemical transformations is an important development in this field, but questions relating to the generality and origin of the effect remain. Here, we demonstrate that these effects can be observed in reactions over a range of bi-metal combinations and reveal the origin of the effect using a combination of electrochemical and materials characterisation. In doing so, we uncover the physicochemical descriptors that (i) dictate whether such effects will be exhibited by a particular combination of supported metal catalysts, and (ii) determine the magnitude of the effect.