Study of palladium nanoparticles prepared from water-in-oil microemulsion

Pd nanoparticles capped by thiol derivatives were prepared in AOT reverse micelles. Studies of UV–vis spectra have indicated that nitrogen purging plays an important role in the formation of Pd nanoparticles while without nitrogen purging results in the formation of Pd(II)–S complexes. Experimental results have also shown that thiolated poly(ethylene glycol) and tiopronin, which could be used to form water-soluble gold nanoparticles, did not favor the formation of isolated water-soluble Pd nanoparticles. However, tiopronin-capped Pd nanoparticles are found to be able to self-organize into nearly spherical aggregates.