Combinatorial Synthesis of Binary Nanoparticles in Ionic Liquids by Cosputtering and Mixing of Elemental Nanoparticles

Abstract

Binary alloy nanoparticles were fabricated by two combinatorial methods: (I) cosputtering from elemental targets into the ionic liquid 1-butyl-3-methylimidazolium bis­(trifluoromethylsulfonyl)­imide [Bmim]­[(Tf)2N] and (II) by mixing elemental nanoparticles after sputtering them separately into [Bmim]­[(Tf)2N]. Both methods lead to the formation of Au–Cu nanoparticles (2.3 nm for cosputtered, 3.6 nm for mixed), however with different resulting compositions: cosputtered nanoparticles show a composition range of Au80–90Cu20–10; mixing of Au- and Cu-loaded ionic liquids leads to the formation of Au75Cu25 nanoparticles. Annealing the binary nanoparticles at 100 °C shows that the mixed nanoparticles grow to sizes of 4.1 nm, whereas the cosputtered nanoparticles grow only to 3 nm.

Up-scaling nanoparticle synthesis by sputter deposition in ionic liquids

“…After deposition, the pieces were stored for 4 h in technical acetone to remove the lift-off photoresist and cleaned afterwards with technical acetone (purity 99.5%) and isopropanol (purity 99.7%). The lm thicknesses was measured with a pro lometer on 27 measurement points revealing a Cu deposition rate of 0.143 nm/s for this chamber con guration, which is approximately 80% higher than the usual Cu rate (0.08 nm/s) used in our standard scienti c chamber con guration (Meischein et al 2019). For the synthesis parameters of the latter Cu NPs obtained from a scienti c sputter deposition (used for comparison issues) see Meischein et al (Meischein et al 2019).…”

“…The NP formation occurs without any stabilization agents and the composition of binary or multinary NPs can be determined by co-sputtering and the speci c sputter rates of the elements controlled by the applied sputtering powers (Hirano et al 2013;König et al 2014). The (multinary) NP formation by sputtering into ILs is not limited to reaction mechanisms and the availability of precursor chemicals since all vacuum compatible chemical elements can be used as target materials for (co-)sputtering (König et al 2014;Meischein et al 2019;Meyer et al 2018).…”

Synthesis of plasmonic Fe/Al nanoparticles in ionic liquids

“…However, the composition of the thin lm and the NPs can deviate. 74 XPS analysis of the lm on the Si substrate was done for further compositional analysis (Table S3, Fig. S16-S18, ESI †).…”

Sputter deposition of highly active complex solid solution electrocatalysts into an ionic liquid library: effect of structure and composition on oxygen reduction activity

“…Traditional wet synthesis routes are suitable for the synthesis of single-element or binary alloys. 16,17 The synthesis of single-phase CSSNPs demands a technique with great control over the nucleation process down to the atomic scale, which can be achieved by combinational co-sputtering into ionic liquids (ILs), 18,19 which offers an almost unlimited flexibility for the used pure elements. ILs are excellent dispersion media to control size, structure and composition of CSSNPs.…”

“…CSSNPs compositions can be defined by co-sputtering of several elements simultaneously from individual targets or by using alloy targets. 18,21 In addition, the desired phase, crystallinity and size of the CSSNPs can be modulated by means of post-annealing treatment. 21 Co-sputtering is a high-through-put deposition technique, which allows for screening, but also upscaling of the production of CSSNPs seems feasible.…”