Growth of Transition-Metal Dichalcogenides by Solvent Evaporation Technique

Due to their physical properties and potential applications in energy conversion and storage, transition-metal dichalcogenides (TMDs) have garnered substantial interest in recent years. Among this class of materials, TMDs based on molybdenum, tungsten, sulfur, and selenium are particularly attractive due to their semiconducting properties and the availability of bottom-up synthesis techniques. Here we report a method which yields high-quality crystals of transition-metal diselenide and ditelluride compounds (PtTe2, PdTe2, NiTe2, TaTe2, TiTe2, RuTe2, PtSe2, PdSe2, NbSe2, TiSe2, VSe2, ReSe2) from their solid solutions, via vapor deposition from a metal-saturated chalcogen melt. Additionally, we show the synthesis of rare-earth-metal polychalcogenides and NbS2 crystals using the aforementioned process. Most of the crystals obtained have a layered CdI2 structure. We have investigated the physical properties of selected crystals and compared them to state of the art findings reported in the literature. Remarkably, the charge density wave transition in 1T-TiSe2 and 2H-NbSe2 crystals is well-defined at TCDW ≈ 200 and 33 K, respectively. Angle-resolved photoelectron spectroscopy and electron diffraction are used to directly access the electronic and crystal structures of PtTe2 single crystals and yield state of the art measurements. © 2020 American Chemical Society.M.A.-H. acknowledges support from the VR starting grant 2018-05339 and KL1824/6. The crystal growth experiments were supported by the Russian Science Foundation, Project 19-12-00414. The work has been supported by the program 211 of the Russian Federation Government agreements 02.A03.21.0006 and 02.A03.21.0011, by the Russian Government Program of Competitive Growth of Kazan Federal University. We acknowledge MAX IV Laboratory for time on Beamline Bloch under Proposal 20190335. Research conducted at MAX IV, a Swedish national user facility, is supported by the Swedish Research council under contract 2018-07152 the Swedish Governmental Agency for Innovation Systems under contract 2018-04969, and Formas under contract 2019-02496. We acknowledge ARPES experiment support from Craig Polley (MAX IV), Maciej Dendzik (KTH) Antonija Grubisic-Cabo (KTH) and Oscar Tjernberg (KTH). H.R., D.P. and G.J.M. acknowledge the Swedish Research Council (2018-06465, 2018-04330) and the Swedish Energy Agency (P43549-1) for financial support

Wettability of amorphous and nanocrystalline Fe78B13Si9 substrates by molten Sn and Bi

The wettability of amorphous and annealing-induced nanocrystalline Fe78B13Si9 ribbons by molten Sn and Bi at 600 K was measured using an improved sessile drop method. The results demonstrate that the structural relaxation and crystallization in the amorphous substrates do not substantially change the wettability with molten Bi because of their invariable physical interaction, but remarkably deteriorate the wettability and interfacial bonding with molten Sn as a result of changing a chemical interaction to a physical one for the atoms at the interface

Long-term clinical results of coronary angioplasty with sirolimus-eluting stents in patients with Type 2 diabetes mellitus

Aim. To assess the long-term results of coronary artery stenting (CAS) with drug-eluting stents (DES) in patients with coronary heart disease (CHD) and Type 2 diabetes mellitus (DM-2).Material and methods. CAS results were analyzed for 99 male and female CHD patients with angina and DM-2. In total, 78 sirolimus-eluting stents were implanted in 53 patients, and 57 non-DES were implanted in 46 individuals. In both groups, lethality and complication incidence were assessed, including the rates of recurrent angina, myocardial infarction, coronary artery bypass graft surgery, repeated endovascular intervention (EI) in the first 12 months after coronary angioplasty and in 2,5 years after EI.Results. DES usage reduced 12-month incidence of severe cardiovascular events (CVE) from 28,9% to 9,4%, and recurrent angina incidence – from 37,8% to 17%. Decrease in severe CVE rates was explained by reduction in repeated CA angioplasty – from 22% to 5,7%. In DES group, reduced long-term incidence was observed for severe CVE – from 40% to 18,9% and recurrent angina – from 44,4% to 22,6%.Conclusion. Endovascular myocardial revascularization with DES reduced 12-month risk of severe CVE and recurrent angina in patients with CHD and DM-2. This positive tendency remained for at least 2,5 years after coronary angioplasty