Hydrogen spillover assisted by oxygenate molecules over nonreducible oxides

Abstract

AbstractSpontaneous migration of atomic hydrogen species from metal particles to the surface of their support, known as hydrogen spillover, has been claimed to play a major role in catalytic processes involving hydrogen. While this phenomenon is well established on reducible oxide supports, its realization on much more commonly used non-reducible oxides is still challenged. Here we present a general strategy to enable effective hydrogen spillover over non-reducible SiO2 with aid of gaseous organic molecules containing a carbonyl group. By using hierarchically-porous-SiO2-supported bimetallic Pt-Fe catalysts with Pt nanoparticles exclusively deposited into the micropores, we demonstrate that activated hydrogen species generated on the Pt sites within the micropores can be readily transported by these oxygenate molecules to Fe sites located in macropores, leading to significantly accelerated hydrodeoxygenation rates on the latter sites. This finding provides a molecule-assisted approach to the rational design and optimization of multifunctional heterogeneous catalysts, reminiscent of the role of molecular coenzymes in bio-catalysis.