(744d) Selective and Highly Stable H2 Production from Formic Acid Decomposition over Graphite-Supported Moc

Formic acid (FA) is a good “green” energy carrier candidate since it can be produced from CO₂, stored as a liquid, and converted to H₂ and CO₂ on demand to power H₂ fuel cells. Several interesting catalytic approaches have been investigated on both ends of this cycle, but the final reforming reaction still needs more work to become a viable commercial fuel source. Unlike the synthesis reaction, which will be conducted at a production plant and can use any materials or processes within the cost and safety limits, the on-demand reforming reaction must meet a number of criteria. First, FA reforming cannot be conducted over expensive, difficult-to-prepare, or unsafe catalysts – for both economic and safety reasons. Any catalyst chosen for a commercial FA reformer must also maintain very good long-term stability, which oftentimes means a loss in activity. We have synthesized MoC nanoparticles (~2 nm) supported on graphite which demonstrate higher FA reforming activity, better CO₂/CO selectivity, and greater long-term stability without H₂ pretreatment than unsupported Mo₂C. We also propose a simple reaction mechanism for both reaction pathways based on previous observations and DFT studies on other materials as well as our own observations, and thoughts on how to further improve the reaction without using expensive or difficult-to-prepare catalysts, including by additive co-feed and with electric fields.