Gold is special:

1. Gold electrodes are advantageous because bulk gold is inert, so electrodes are air/water stable (do not oxidise).
2. Gold nanoparticles can be used as a catalyst (high surface to volume ratio, unlike bulk gold), for filtering purposes for example.
3. Gold nanoparticles change color as a function of nanoparticle diameter (30-90 nm), making it useful in quantum dot applications.
4. Melting temperature of gold nanoparticles is relatively low (~300C), making it susceptible to thermal pre/post treatment.
5. Gold can be easily functionalized using thiol (sulfur) groups, for example, making it possible to design adsorption behaviour and even self-assembly.
6. Absorption spectrum of gold nanoparticles can be tweaked by modifying the size of the nanoparticles, which influences on gold's conversion of light to heat. This can be used to thermally kill tumours.

Gold is special:

1. Electrodes: gold electrodes are advantageous because bulk gold is inert, so electrodes are air/water stable (do not oxidise), such that devices are more reliable in the long term.
2. Catalyst: gold nanoparticles can be used as a catalyst (high surface to volume ratio, unlike bulk gold), for filtering purposes for example.
3. Quantum dots: gold nanoparticles change color as a function of nanoparticle diameter (30-90 nm), making it useful in quantum dot applications.
4. Low melting temperature: melting temperature of gold nanoparticles is relatively low (~300C), making it susceptible to thermal pre/post treatment.
5. Easy functionalization: gold can be easily functionalized using thiol (sulfur) groups, making it possible to design adsorption behaviour and self-assembly.
6. Conversion of light to heat: the absorption spectrum of gold nanoparticles can be tweaked by modifying the size of the nanoparticles, which influences on gold's conversion of light to heat. This can be used to thermally kill tumours.