Thickness-dependent properties of ultrathin bismuth and antimony chalcogenide films formed by physical vapor deposition and their application in thermoelectric generators

Abstract

In this work, a simple cost-effective physical vapor deposition method for obtaining high-quality Bi 2 Se 3 and Sb 2 Te 3 ultrathin films with thicknesses down to 5 nm on mica, fused quartz, and monolayer graphene substrates is reported. Physical vapor deposition of continuous Sb 2 Te 3 ultrathin films with thicknesses 10 nm and below is demonstrated for the first time. Studies of thermoelectrical properties of synthesized Bi 2 Se 3 ultrathin films deposited on mica indicated opening of a hybridization gap in Bi 2 Se 3 ultrathin films with thicknesses below 6 nm. Both Bi 2 Se 3 and Sb 2 Te 3 ultrathin films showed the Seebeck coefficient and thermoelectrical power factors comparable with the parameters obtained for the highquality thin films grown by the molecular beam epitaxy method. Performance of the best Bi 2 Se 3 and Sb 2 Te 3 ultrathin films is tested in the two-leg prototype of a thermoelectric generator.

Flexible N-Type Thermoelectric Composites Based on Non-Conductive Polymer with Innovative Bi2Se3-CNT Hybrid Nanostructured Filler

“…Bi 2 Se 3 nanostructures were deposited on prefabricated surfaces by a spray-coating technique MWCNT substrate by catalyst-free physical vapour deposition method described elsewhere [ 18 , 19 , 22 , 23 , 24 ]. The mass fraction of the deposited Bi 2 Se 3 material on the MWCNT networks was varied by the amount of the source material and deposition time.…”

“…Thermoelectrical measurements were carried out at room temperature (300 K) under ambient conditions using a home-made device allowing bending of the samples and calibrated by Standard Reference Material 3451 (NIST, Gaithersburg, MD, USA) for a low-temperature Seebeck coefficient as described elsewhere [ 24 ]. Room-temperature electrical characterization was performed using Keithley 6430 Sub-Femtoamp Remote Source Meter (Cleveland, OH, USA).…”

Correlation analysis of vibration modes in physical vapour deposited Bi2Se3 thin films probed by the Raman mapping technique

“…where growth occurs not layer-by-layer, but by the formation of separate islands, which subsequently coalesce. 6,26,29 Indeed, the Volmer-Weber growth mechanism of Bi 2 Se 3 lms leads to the appearance of strain which is mainly concentrated in the grooves between the grains. In the case of strong interaction of the deposited material with the substrate, this type of strain is considered to be hydrostatic.…”

“…Various devices for electronic, spintronic and even domestic waste heat conversion applications can be realised based on graphene/TI heterostructures. [1][2][3][4][5][6] Although the physical properties of these 2D materials are rather well understood, their wide practical applications are still challenging due to the extreme sensitivity of these materials to the substrates they are supported by. Strain is one of the most prominent phenomena occurring at the interface of the contacting materials which can change their band structure.…”

High-Yield Growth and Tunable Morphology of Bi2Se3 Nanoribbons Synthesized on Thermally Dewetted Au

“…Bi 2 Se 3 nanoribbons can reach lengths of tens of micrometers and even millimeters [ 15 ], allowing one to easily make multiple electrical connections to probe topological transport properties, as well as can serve as field-effect transistor channels [ 16 ] and active elements in nanoelectromechanical devices [ 17 , 18 ]. Successful applications of Bi 2 Se 3 nanostructures as nanowires and nanoribbons have been demonstrated in the areas of thermoelectrics [ 19 , 20 , 21 ], photodetection [ 22 ], topological insulator devices [ 23 , 24 , 25 ], and nanoelectromechanical devices [ 17 , 18 ].…”