Gold
Introduction
Gold nanoparticles have been extensively studied because of their use in catalysis and photothermal heating. The catalytic activity of gold is remarkable, because bulk gold is chemically inert. Gold nanoparticles can even catalyze oxidation reactions below room temperature. The unsaturated bonds at the surface enable reactions to take place, but it is not clear how the mechanism works exactly.
Apart from the different coordination numbers of the gold atoms at the surface, there is also a distinct electronic contribution. Small nanoparticles with only a few hundred atoms do not share the same metallic properties from the bulk. The metal-insulator transition at room temperature is expected to occur around 442 atoms. This corresponds to the particle size where the maximum catalytic activity is observed, around 2 nm.
Basic data
| Name | Gold (Au) |
|---|---|
| Configuration | 6s1 5d10 4f14 |
| Electrons | 79 |
| Group | 11 |
| Abundance | Negligible |
| Magnetic type | Diamagnetic |
| Melting point | 1064 ℃ |
| Boiling point | 2856 ℃ |
Interesting reads
- Generation of nanoparticles by spark discharge synthesis doi:10.1007/s11051-008-9407-y
- Catalytic activity of Au nanoparticles functionality doi:10.1016/S1748-0132(07)70113-5
Key trends at the nanoscale
Applications
The pie chart presented here is based on the distribution of research literature across various fields of application research over the period 1992 to 2017. The value listed is the number of papers discussing Gold related to nanoparticles, sorted by application field. This gives an indication which applications are being or have been researched and where the core interest is. However, the distribution does not correct for the total publications in a given application field. So, a high score for a given application field indicates there is considerable interest in the element in that field, but it may also mean the field itself has considerable more publications than other fields. Therefore, the pie chart gives a general overview only. The application fields themselves are discussed in more detail on our Nanoparticles page.
Additionally, the total number of publications provides some insight in the amount of research into Gold used in nanoparticles in general. Typically, a well-researched element will show 1000 or more publications over the 1992-2017 period.
Alloys and composites
The graph below presents an analysis of literature on core-shell, alloy and composite particles with gold as a component of such nanoparticles. It shows possible combinations for alloy or composite nanoparticles and reflects research interest during the 1992-2017 period.