One-Pot Synthesis of In0 Nanoparticles with Tuned Particle Size and High Oxidation Stability

In-0 nanoparticles with tunable size are obtained via NaBH4-induced reduction of InCl3 center dot 4H(2)O in diethylene glycol. Citrate-capping allows nucleating almost monodisperse and non-agglomerated In-0 nanoparticles. Effective size tuning is possible in a wide range (10-100 nm) just by varying the concentration of NaBH4, resulting in mean diameters of 8, 55, and 105 nm. The citrate-capped In-0 nanoparticles, moreover, turn out as surprisingly stable against air oxidation. According to XRD and SEM analysis, the 8 nm-sized In-0 particles are molten at room temperature. Size-dependent evolution of the plasmon resonance is observed and results in a brownish-red color and a distinct absorption in the case of the smallest In-0 particles.