Organics- and Surfactant-Free Molten Salt Medium Controlled Synthesis of Pt-M (M = Cu and Pd) Bi- and Trimetallic Nanocubes and Nanosheets

Abstract

We present a novel synthetic strategy for the shape-controlled synthesis of Pt-based alloy nanoparticles (NPs) in inorganic molten salt without using any organic surfactants or capping agents. Graphene oxide (GO) was chosen as the stabilizer in the inorganic molten salt synthetic strategy, due to the existence of various oxygen-containing functional groups on its surface, which adsorb, anchor, and stabilize the metal ions or NPs. After GO was added in molten salt, the PtPd nanosheets were formed on its surface in H 2 atmosphere. In addition, when KI was chosen as the shape-inducing agent to selectively adsorb on and fully protect the (100) facets of alloys, PtPd nanocubes with core−shell structure, PtCu nanohemicubes, and PtPdCu nanocubes were prepared successfully on the surface of GO in molten salt. Introduction of GO as the stabilizer in molten salt proves a new approach in synthesis of Pt-based nanocrystals with controlled morphologies.

Recent Developments on Molten Salt Synthesis of Inorganic Nanomaterials: A Review

“…While the synthesis of intermetallic nanocrystals has been a huge challenge to materials scientists, the reports on intermetallic nanocrystals of Pt 3 Y, Pt 3 Sc, Pt 3 Lu, Pt 2 Na, and Au 2 Y, etc. have demonstrated that the MSS is an effective synthesis approach and should be further explored for them. , …”

“…have demonstrated that the MSS is an effective synthesis approach and should be further explored for them. 328,329 Molten salts and ionic liquids, which in general are composed of simple ionic pairs and large ionic species and are used in high and low temperature ranges, respectively, seem to be going in opposite directions in the plethora of the syntheses of nanomaterials. 330 It can be a boon to ionic liquid researchers if both empirical and theoretical knowledge of molten salt chemistry can be transferred to them or vice versa.…”

Properties of Negatively Charged Ruthenium Clusters in Molten Sodium Chloride

“…Metal nanoparticles suspended in molten salt media [1][2][3] can be obtained by reducing their corresponding cations (as halides or oxides) in a mixture with a non-reducible molten salt using hydrogen gas, 4 or an alkali metal. [5][6][7] The reduction potential of alkali metal dissolved in molten alkali halide salts is so large that the alkali atoms ionize to alkali ions and solvated electrons.…”

Single atom catalysts by atomic diffusion strategy

“…Not only that, this method can also effectively control the morphology of the product. Qiu et al [102] added GO to molten salt, used KI as a shape inducer, and synthesized Pt Pd nanocubes with a core-shell structure on the GO surface. The above shows that the melten salt method has a simple synthesis process and a relatively mild reaction temperature, making it easier to realize industrialization.…”