A simple gram-scale synthesis of Pd–Fe₃O₄ heterodimer nanocrystals was achieved by controlled one-pot thermolysis of a mixture solution composed of iron acetylacetonate, palladium acetylacetonate, oleylamine, and oleic acid. The heterodimer nanocrystals are composed of a 6 nm-sized Pd nanosphere and a 30 nm-sized faceted Fe₃O₄ nanocrystal and they are soft ferrimagnetic with high saturation magnetization value and low coercivity value. The heterodimer nanocrystals exhibited good activities for various Suzuki coupling reactions. Furthermore, the nanocrystal catalyst could be easily separated from the product mixture by using a magnet and could be recycled 10 times without losing catalytic activity.

A simple synthesis of Rh–Fe₃O₄ heterodimer nanocrystals was achieved by controlled one-pot thermolysis. The nanocrystals exhibited excellent activities for the selective reduction of nitroarenes and alkenes. Furthermore the nanocrystal catalyst could be easily separated by a magnet, and recycled eight times without losing the catalytic activity.