2. Applications in heterogeneous catalysis

Because of their nanometric size, metal nanoparticles have different physical and chemical properties to those of macroscopic metals or mononuclear metal complexes.

For example, gold usually melts at T _M = 1064°C at atmospheric pressure. On the nanoparticle scale, however (from 0 to 250 nm, for example), its melting temperature increases with size, following a curve that tends towards T _M (figure 3 ).