Vapor-phase preparation of gold nanocrystals by chloroauric acid pyrolysis

Abstract We report that gold nanocrystals can be prepared from vapor phase using chloroauric acid (HAuCl 4 ) as the precursor. By tuning the vapor-phase deposition parameters, the size and space distribution of the gold nanocrystals can be well controlled on substrates. Systematic control experiments demonstrate that intermediate AuCl and AuCl 3 products pyrolyzed from HAuCl 4 play an essential role in this vapor-phase deposition process. Compared to conventional wet-chemical synthesis process, vapor-phase process enables direct deposition of gold nanoparticles on solid substrates with better coverage and uniformity, which may find applications in surface-enhanced Raman scattering and plasmon-enhanced photocatalysis.