[3Ca01-12] SS2

[3Ca10S] Formic acid synthesis by CO₂ hydrogenation using Pd nanocatalyst modified with GaO_X

*Hiroto Hata¹, Kohsuke Mori^1,2, Hiromi Yamashita ^1,2 (1. Graduate School of Engineering, Osaka University, 2. Elements Strategy Initiative for Catalysts and Batteries, Kyoto University)

In this study, we have developed Pd nanocatalysts modified with Group 13 elements (Ga, Al, B), which promote hydrogenation of carbon dioxide to formic acid. According to the HAADF-STEM and XAFS, it is found that Group 13 elements exist on Pd nanoparticle as oxide cluster. We demonstrated that the modification with GaO_X enhanced the catalytic activity based on the surface exposed Pd, which was ten times higher than that of the unmodified Pd catalyst. Kinetic and DFT calculation indicate that ensemble Pd sites with different charge balances, which is caused by the partial modification with GaO_X, can promote not only the hydrogen dissociation but also the adsorption of HCO₃^- species and hydrogenation of HCO₃^- species.