Hydrogenation of carbon dioxide to formic acid over Pd doped thermally activated Ni/Al layered double hydroxide

Our report here describes the catalytic reduction of CO2 to formic acid by PdNi bimetallic species supported on layered double hydroxides (referred here as LDO). The catalysts were characterized by physicochemical and spectroscopic techniques such as XRD, FT-IR, XPS, TEM, SEM, BET, ICP and TPD analysis. The catalysts were active for reduction of CO2 to formate under alkaline medium. In particular, Pd-Ni LDO catalyst with high Ni to Pd atomic ratio not only showed significantly improved catalytic activity (256 TON) but also maintained robust nature for multiple catalytic cycles (5th catalytic run) with no leaching of active metals. Further, on the basis of density functional theory (DFT) calculations, effect of Pd doping on the catalytic performance of Ni-LDO was discussed. This work provides an interesting and effective strategy wherein addition of precious metal Pd in small amounts (up to 0.5 wt%) on Ni-LDO is sufficient to improve the catalytic performance.