LM-I-12
Synthesis by laser ablation in liquid of alloy nanoparticles: controlling the structure and the composition for specific
applications
V. Amendola1
1- University of Padova, Department of Chemical Sciences 1, Via Marzolo I-35131 Padova - ITALY Main author email address: vincenzo.amendola@unipd.it
Laser ablation in liquid (LAL) emerged as a powerful technique for the production of nanoparticles (NPs) with peculiar surface chemistry and a large variety of compositions, included metastable phases and nanocomposites, all by the same self standing and simple set up.[1-2] Currently, several efforts are undergoing to improve the control on laser generated nanomaterials and to precisely understand the formation mechanism of NPs.[1,3,4] As part of these efforts, a whole catalogue of alloy NPs was accessible for fundamental studies about the structural motifs adopted by elements frozen at the nanoscale and the consequent set of physical-chemical properties. The insights on the structure-properties relation provided the basis for further optimization of the nanoalloys for specific applications. The cases of alloys designed to climb the volcano plot for specific electrocatalytic processes,[5,6] alloys where the coexistence of magnetic and plasmonic properties is engineered,[7,8] and noble metal alloys acting as 4-D multimodal contrast agents with enhanced clearance from the body[9] will be discussed. This is a general demonstration of the range of innovative results and functional optimization expected by the synergy between LAL synthesis, structural modelling, and
experimental (A)
verification of functional
properties
in nonequilibrium
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uj 4 I
OL 3
nanoalloys. ^^ (C)
Figure 1. (A) Iron-rich Au-Fe nanoalloys are obtained in ethanol by nanosecond laser ablation of a bilayer Au/Fe film (left). When the same film is ablated in water, core-shell NPs of iron oxide-AuFe metal alloy (iron poor) are achieved.[3,4] These NPs possess interesting properties for photonics (B), exhibiting localized surface plasmons,[8] and for catalysis (C), with enhanced activity compared to single element analogues[5].
[1] V. Amendola et al., Room-Temperature Laser Synthesis in Liquid of Oxide, Metal-Oxide Core-Shells, and Doped Oxide Nanoparticles, Chem. Eur. J., 26, 9206 - 9242 (2020).
[2] S. Crivellaro et al., A system for the synthesis of nanoparticles by laser ablation in liquid that is remotely controlled with PC or smartphone, Rev. Sci. Instr., 90, 033902, (2019).
[3] V. Amendola et al.; Formation of alloy nanoparticles by laser ablation of Au/Fe multilayer films in liquid environment, J.Coll.Interf.Sci., 489, 18-27, (2017).
[4] A. Tymoczko et al., One-step synthesis of Fe-Au core-shell magnetic-plasmonic nanoparticles driven by interface energy minimization, Nanoscale Horiz., 4, 1326-1332, (2019).
[5] I. Vassalini et al., Enhanced Electrocatalytic Oxygen Evolution in Au-Fe Nanoalloys, Angew. Chem., 56, 6589-6593, (2017).
[6] R. Brandiele et al., Climbing the oxygen reduction reaction volcano plot with laser ablation synthesis of PtxY nanoalloys, Catal. Sci. Technol., 10, 4503-4508 (2020).
[7] V. Amendola et al., Laser generation of iron-doped silver nanotruffles with magnetic and plasmonic properties, Nano research 8, 40074023, (2015).
[8] D. Alexander et al., Electronic Structure-Dependent Surface Plasmon Resonance in Single Au-Fe Nanoalloys, Nano Lett., 19, 5754-5761, (2019).
[9] V. Torresan et al., 4D Multimodal Nanomedicines Made of Nonequilibrium Au-Fe Alloy Nanoparticles ACS Nano 14, 12840-12853 (2020).