Felix Hansen, Rico Fucke, Titouan Charvin, Samuel Froeschke, Daniel Wolf, Romain Giraud, Joseph Dufouleur, Nico Gräßler, Bernd Büchner, Peer Schmidt, Silke Hampel
- The tellurides of bismuth and antimony (Bi2Te3 and Sb2Te3) are prominent members of the V2VI3 material family that exhibit promising topological properties. We provide a method for the rational synthesis of mixed crystals of these materials ((BixSb1–x)2Te3 with x = 0.1, ..., 0.9) by means of a bottom-up chemical vapor transport (CVT) approach. Thermodynamic calculations showed the synthesis to be possible in the temperature range of 390–560 °C without significant enrichment of either component and without adding a transport agent. The starting materials were synthesized and verified by X-ray diffraction (XRD). Optimization experiments showed the ideal conditions for nanosheet synthesis to be T2 = 560 °C, T1 = 390 °C with a reaction time of t = 36 h. Crystals with heights of down to 12 nm (12 quintuple layers) were synthesized and analyzed by means of scanning electron microscopy, energy-dispersive X-ray spectrometry, and atomic force microscopy. High-resolution transmission electron microscopy confirmed the R3̅m crystal structure,The tellurides of bismuth and antimony (Bi2Te3 and Sb2Te3) are prominent members of the V2VI3 material family that exhibit promising topological properties. We provide a method for the rational synthesis of mixed crystals of these materials ((BixSb1–x)2Te3 with x = 0.1, ..., 0.9) by means of a bottom-up chemical vapor transport (CVT) approach. Thermodynamic calculations showed the synthesis to be possible in the temperature range of 390–560 °C without significant enrichment of either component and without adding a transport agent. The starting materials were synthesized and verified by X-ray diffraction (XRD). Optimization experiments showed the ideal conditions for nanosheet synthesis to be T2 = 560 °C, T1 = 390 °C with a reaction time of t = 36 h. Crystals with heights of down to 12 nm (12 quintuple layers) were synthesized and analyzed by means of scanning electron microscopy, energy-dispersive X-ray spectrometry, and atomic force microscopy. High-resolution transmission electron microscopy confirmed the R3̅m crystal structure, high crystallinity, and overall quality of the synthesized (BixSb1–x)2Te3 nanosheets. Magnetotransport measurements revealed that such ternary compounds can have a significantly reduced carrier density compared to the binary parent compounds.…