An easy way of such synthesis is by wet chemical precipitation process. Step I should be reduction of the metal salt by any known reducing agent (LiAlH4, NaBH4 etc.). Then, step II is to introduce the reduced metal (high reactivity in nano dimensions) to a strong oxidizing agent (NaOCl, (CaOCl)Cl, KMnO4 etc.) It is expected that the metallic surface will develop a steady layer of metal (having functionalized by peroxide bonds). The number of peroxide bonds will depend on the strength of the oxidizing agent and its exposure time. The nanoparticle will either be self stabilized (as in case of Ni) or will have to be capped using capping agents like PVP or CNC. 

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