Deposit of UV- or γ-synthesized gold nanoparticles on TiO2 powder using lipid-based multilamellar vesicles

This article describes a general method for the deposition of gold nanoparticles onto solid support based on the use of multilamellar vesicles (MLVs). Gold nanoparticles (nps) synthesized within lipid-based MLVs by UV- or γ-irradiation were deposited onto TiO₂ powder support. The organic phase from MLVs was removed by calcination leading to high dispersion of naked Au nanoparticles. The resulting particles were investigated using spectrometry, electron microscopy and XPS. The gold nanoparticles were stable and well-separated on the titania surface. It was found that the metal nanoparticles produced by radiolysis have smaller average size and narrower size distribution than those synthesized by photochemical route. After calcinations, the particles tended to enlarge to reach c.a. 18 nm. The gold loading on the titania support could be controlled by changing the gold salt concentration and the MLV-to-TiO₂ weight ratio; values of Au-to-Ti ratio up to 44 % could be obtained.