TY - GEN A1 - Froeschke, Samuel A1 - Wolf, Daniel A1 - Hantusch, Martin A1 - Giebeler, Lars A1 - Wels, Martin A1 - Gräßler, Nico A1 - Büchner, Bernd A1 - Schmidt, Peer A1 - Hampel, Silke T1 - Synthesis of micro- and nanosheets of CrCl3–RuCl3 solid solution by chemical vapour transport T2 - Nanoscale N2 - Solid solutions of 2D transition metal trihalides are rapidly growing in interest for the search for new 2D materials with novel properties at nanoscale dimensions. In this regard, we present a synthesis method for the Cr1−xRuxCl3 solid solution and describe the behaviour of the unit cell parameters over the whole composition range, which in general follows Vegard's law in the range of a = 5.958(6)CrCl3 … 5.9731(5)RuCl3 Å, b = 10.3328(20)CrCl3 … 10.34606(21)RuCl3 Å, c = 6.110(5)CrCl3 … 6.0385(5)RuCl3 Å and β = 108.522(15)CrCl3 … 108.8314(14)RuCl3 °. The synthesized solid solution powder was subsequently used to deposit micro- and nanosheets directly on a substrate by applying chemical vapour transport in a temperature gradient of 575 °C → 525 °C for 2 h and 650 °C → 600 °C for 0.5 h as a bottom-up approach without the need for an external transport agent. The observed chromium chloride enrichment of the deposited crystals is predicted by thermodynamic simulation. The results allow for a nanostructure synthesis of this solid solution with a predictable composition down to about 30 nm in height and lateral size of several μm. When applying a quick consecutive delamination step, it is possible to obtain few- and monolayer structures, which could be used for further studies of downscaling effects for the CrCl3–RuCl3 solid solution. X-ray photoelectron spectroscopy, transmission electron microscopy and Raman spectroscopy were used to confirm the purity and quality of the synthesized crystals. KW - Crystal growth KW - Chemical vapor transport KW - Thermal analysis KW - Thermodynamic modeling KW - 2D layered compounds Y1 - 2022 UR - https://pubs.rsc.org/en/content/articlelanding/2022/NR/D2NR01366E U6 - https://doi.org/10.1039/D2NR01366E SN - 2040-3372 VL - 29 IS - 14 SP - 10483 EP - 10492 ER - TY - GEN A1 - Froeschke, Samuel A1 - Yasmen, Nadia A1 - Popov, Alexey A1 - Schiemenz, Sandra A1 - Wolf, Daniel A1 - Giebeler, Lars A1 - Hantusch, Martin A1 - Gräßler, Nico A1 - Büchner, Bernd A1 - Schmidt, Peer A1 - Hampel, Silke T1 - Controlled Nanoplatelet Deposition of 2D Chromium Trihalide Solid Solutions T2 - Chemistry of Materials N2 - The two-dimensional (2D) chromium trihalides CrCl3, CrBr3, and CrI3 are most famous for their exotic magnetic properties when their crystals get downscaled to nanometer dimensions. One way to tune the properties of such materials and to further increase their potential utility, e.g., in spintronics, is the formation of solid solutions. Here, we present a detailed theoretical and experimental study on the synthesis and nanoplatelet growth of CrBrxCl3–x and CrBrxI3–x solid solutions. Phase pure powder was obtained by tempering the respective parent compounds at 600 and 550 °C, using additional iodine in the case of CrBrxI3–x. The dominant stacking order changes at x = 1.8 for CrBrxCl3–x while remaining similar to CrI3 for the whole CrBrxI3–x series. A consecutive chemical vapor transport from 575 → 525 °C for 2 h (CrBrxCl3–x) or 600 → 550 °C for 3 h with 0.1 mmol additional iodine (CrBrxI3–x) resulted in the deposition of high-quality nanoplatelets on a substrate with only several nanometers in height. The composition can be controlled by the choice of the starting material, since only small shifts in the anion ratio occur during the transport. The deposited CrBrxCl3–x nanoplatelets can then be easily delaminated by ultrasonication in ethanol to reduce the height even further to few-layer dimensions. These nanoplatelets could potentially be used to investigate the property changes (e.g., in terms of magnetic response) for the downscaling of these solid solutions. We further demonstrate the quality of the deposited material by transmission electron microscopy, selected area electron diffraction, and X-ray photoelectron spectroscopy. Raman spectroscopy of the solid solution series reveals a complex evolution of vibrational modes. Photoluminescence measurements on solid solution samples show emission peaks in the near-infrared energy range with the specific energy and intensity being composition and temperature dependent. KW - 2D layered compounds KW - Chemical vapor transport KW - Crystal growth KW - Crystal structure KW - Halides KW - Thermodynamic modeling Y1 - 2023 UR - https://pubs.acs.org/doi/full/10.1021/acs.chemmater.2c03785 U6 - https://doi.org/10.1021/acs.chemmater.2c03785 SN - 1520-5002 SN - 0897-4756 VL - 35 IS - 11 SP - 4136 EP - 4148 ER -