Ruthenium

Zero-Valent Reaction:

Synthesis Setup:

Chemicals:

Ruthenium (III) chloride hydrate, Stannous chloride, acetone

Procedure:

Stannous chloride (SnCl2) is an excellent reducing agent and can be used to reduce many of the metal chlorides to a zero-valent species. The electrochemical redox potential favors oxidation of the tin halide and reduction of the metal halide.

Redox Potentials: SnCl2 → SnCl4   -0.1375   Rh2+ + 2e- → Rh(0)   0.455     Total: 0.5925

This reaction will favor formation of Ru(0) and SnCl4 but just barely. Repeated intercalation reactions can get more in.

There is no need to prepare the glassware before intercalation. Setup the reflux apparatus as shown in Fig 2. There is also no need to use an air-free setup. Prepare a stock solution of stannous chloride from 0.014 g of SnCl2 in 5 mL.

Heat a solution of 0.01 g ruthenium(III) chloride in 5 mL acetone in the round-bottom flask (Fig 1) to just below reflux (48°C). Once heated, drop the 2D material, free or suspended on a substrate, into the round bottom flask. Dropwise, add in the solution of tin(II) chloride very slowly over the course of 3 hours. Keep heating during this time at just below reflux. After 3 hours, and complete injection of the stannous chloride solution, wait an additional 30 – 45 mins with heating. After, remove the substrate or 2D crystal from solution and rinse with acetone or ethanol several times. Rinsing with heated acetone (~45°C) will help remove any other salt impurities that may end up on the substrate.

How much can be intercalated into Bi2Se3 nanoribbons:

RuCl3 SnCl2 acetone time ~ intercalated in Bi2Se3 0.01 g 0.014 g 10 mL 3.5 hours 4 atm % ± 2%

Relevant Publications:

M. Wang, D. Williams, G. Lahti, S. Teshima, D. Dominguez-Aguilar, K. J. Koski, Chemical intercalation of heavy metal, semimetal, and semiconductor atoms into 2D layered chalcogenides. 2D Materials, 5, 045005 (2018)

Supported by NSF DMR-1658019