Core–shell nanoheterodimers: laser-assisted deposition of single bimetallic Au@M (M = Au, Ag, Pd, Pt) nanodots on TiO₂ nanoparticles

Fenghuan Zhao (1, 2) , Qingguo Bai (1, 2) , Chenghui Xia (3) , Junjie Hao (1, 2) , Marion Gayot (4) , Jean-Pierre Delville (2) , Marie-Helene Delville (1)

1 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux
2 LOMA - Laboratoire Ondes et Matière d'Aquitaine
3 OUC - Ocean University of China
4 PLACAMAT - Plateforme Aquitaine de Caractérisation des Matériaux

We propose to synthesize well-controlled core-shell nanoheterodimers (NHDs) based on single bimetallic Au@M (M = Au, Ag, Pd, Pt) nanodots (BNDs) grown on bare TiO 2 nanoparticles (NPs) by a two-step laser-assisted deposition. The high photon flux emitted by a focused UV laser triggers nucleation and growth of a single core nanodot (ND) and its size is quantitatively controlled by varying the time exposure and the concentration of gold ions in the solution in the first step. A second laser deposition is performed after adding a new metal precursor to the Au-TiO 2 NHDs thus prepared. Due to the vectorial nature of the first Au-TiO 2 NHDs when photo-excited, and thus the subsequent efficient carrier separation, the second photodeposition strictly takes place on the first gold NDs. Growth is epitaxial for both

Domaines: Matériaux

Fenghuan Zhao, Qingguo Bai, Chenghui Xia, Junjie Hao, Marion Gayot, et al.. Core–shell nanoheterodimers: laser-assisted deposition of single bimetallic Au@M (M = Au, Ag, Pd, Pt) nanodots on TiO₂ nanoparticles. Materials Advances, 2023, 4 (2), pp.694-708. ⟨10.1039/d2ma01018f⟩. ⟨hal-03952671⟩