| Summary: | Zinc-included intermetallic compound catalysts of RhZn, PtZn, and PdZn with a molar ration of Zn/metal = 1/1, which are generally prepared using a hydrogen reduction approach, are known to show excellent catalytic performance in some selective hydrogenations of organic compounds. In this study, in order to reduce the incorporated mounts of the expensive noble metals, we attempted to prepare zinc-rich intermetallic compounds via a CaH<sub>2</sub>-assisted molten salt synthesis method with a stronger reduction capacity than the common hydrogen reduction method. X-ray diffraction results indicated the formation of RhZn<sub>13</sub> and Pt<sub>3</sub>Zn<sub>10</sub> in the samples prepared by the reduction of ZnO-supported metal precursors. In a hydrogenation reaction of <i>p</i>-nitrophenol to <i>p</i>-aminophenol, the ZnO-supported RhZn<sub>13</sub> and Pt<sub>3</sub>Zn<sub>10</sub> catalysts showed a higher selectivity than the RhZn/ZnO and PtZn/ZnO catalysts with the almost similar conversions. Thus, it was demonstrated that the zinc-rich intermetallic compounds of RhZn<sub>13</sub> and Pt<sub>3</sub>Zn<sub>10</sub> could be superior selective hydrogenation catalysts compared to the conventional intermetallic compound catalysts of RhZn and PtZn.
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