Turning on Low-Temperature Catalytic Conversion of Biomass Derivatives through Teaming Pd1 and Mo1 Single-Atom Sites.

On-purpose atomic scale design of catalytic sites, specifically active and selective at low temperature for a target reaction, is a key challenge. Here, we report teamed Pd1 and Mo1 single-atom sites that exhibit high activity and selectivity for anisole hydrodeoxygenation to benzene at low temperatures, 100-150 °C, where a Pd metal nanoparticle catalyst or a MoO3 nanoparticle catalyst is individually inactive. The catalysts built from Pd1 or Mo1 single-atom sites alone are much less effective, although the catalyst with Pd1 sites shows some activity but low selectivity. Similarly, less dispersed nanoparticle catalysts are much less effective. Computational studies show that the Pd1 and Mo1 single-atom sites activate H2 and anisole, respectively, and their combination triggers the hydrodeoxygenation of anisole in this low-temperature range. The Co3O4 support is inactive for anisole hydrodeoxygenation by itself but participates in the chemistry by transferring H atoms from Pd1 to the Mo1 site. This finding opens an avenue for designing catalysts active for a target reaction channel such as conversion of biomass derivatives at a low temperature where neither metal nor oxide nanoparticles are.