Electrodeposition and characterization of thermoelectric Bi2Se3 thin films

Abstract

Bi 2 Se 3 thin films were electrochemically deposited on Ti and indium tin oxide-coated glass substrates, respectively, at room temperature, using Bi(NO 3 ) 3 ·5H 2 O and SeO 2 as starting materials in diluted HNO 3 solution. A conventional three-electrode cell was used with a platinum sheet as a counter electrode, and a saturated calomel electrode was used as a reference electrode. The films were annealed in argon atmosphere. The influence of cold isostatic pressing before annealing on the microstructure and thermoelectric properties of the films was investigated. X-ray diffraction analysis indicates that the film grown on the indium tin oxide-coated glass substrate is pure rhombohedral Bi 2 Se 3 , and the film grown on the Ti substrate consists of both rhombohedral and orthorhombic Bi 2 Se 3 .

Growth and characterization of Bi2Se3 thin films by pulsed laser deposition using alloy target

“…The carrier density in the Bi 2 Se 3 thin films of this work is in the order of 10 21 cm −3 , which is higher than the values reported in the literatures. The carrier density is in the order of 10 19 cm −3 in Bi 2 Se 3 films prepared by electrodeposition, by MOCVD and by rational design of the precursor solution [11,[18][19][20]. The Hall mobility in Bi 2 Se 3 films of this work has the same order of magnitude with the values reported in the literatures except for Bi 2 Se 3 films prepared by MOCVD, in which the mobility is about an order of magnitude higher than the others.…”

“…When the substrate temperature is higher than 200°C, the deposited films show a pure rhombohedral phase of Bi 2 Se 3 . Considering the two different phases of Bi 2 Se 3 , the most reported structure in the literature is the rhombohedral structure [8,[10][11][12][13]. Little data are available on the orthorhombic phase of Bi 2 Se 3 [6,7,9].…”

“…The techniques used for deposition of the Bi 2 Se 3 films are dominated by chemical processes [6][7][8][9][10][11][12]. Physical processes are rarely used for depositing Bi 2 Se 3 films, only the evaporation technique has been used until now [13,14].…”

Potential Thermoelectric Performance from Optimization of Hole-DopedBi2Se3

“…Bi 2 Se 3 ordinarily forms n-type specimens, so that more literature on n-type is available. Typical n-type mobilities at or even somewhat above these concentrations [35][36][37][38][39][40][41] are in this range or higher, so that assuming no great asymmetry in n-type vs p-type scattering rates, the assumed p-type mobilities are reasonable. The assumed carrier concentration dependence implies that mobility increases significantly as carrier concentration decreases, which is generally true until one reaches a limiting value, as in Ref.…”

Simulation on Flow Field and Mixing Phenomenon in Single Snorkel Vacuum Degasser

“…However, the circulation flow rate is mainly determined by the lifting gas flow rate. [1][2][3][4][5] After reaching its maximum value, the circulation flow rate can hardly be increased, and the mixing time can hardly be decreased. [6,7] Hence, to increase the saturation circulation flow rate becomes the key step for improving the productivity.…”