Preparation of Bi4Te3 highly oriented nanopillars array film with enhanced electrical properties

The Bi4Te3 films with well-ordered orientation and microstructure were successfully prepared on SiO2 substrate by a vacuum thermal evaporation deposition technique for the first time. We discussed the effects of evaporation temperature and substrate temperature on the phase and its well-ordered growth of Bi4Te3 films. The formation of Bi4Te3 phase is owing to the differences of the saturated vapor pressure. The thermoelectric transport properties of the Bi4Te3 films were investigated and the (00l)-oriented nanopillars array film has a better electrical transport performance, whose value of PF is 0.032 mWm−1 K−2 at 339 K, approaching twice that of the non-oriented ordinary film. The enhanced electrical properties of Bi4Te3 films could be achieved via the high-crystallinity well-controlled (00l)-oriented nanopillars array.

Download Full-text

Study on a Quaternary Working Pair of CaCl2-LiNO3-KNO3/H2O for an Absorption Refrigeration Cycle

Entropy ◽

10.3390/e21060546 ◽

2019 ◽

Vol 21 (6) ◽

pp. 546 ◽

Cited By ~ 2

Author(s):

Yiqun Li ◽

Na Li ◽

Chunhuan Luo ◽

Qingquan Su

Keyword(s):

Heat Capacity ◽

Crystallization Temperature ◽

Saturated Vapor Pressure ◽

Saturated Vapor ◽

Specific Enthalpy ◽

Refrigeration Cycle ◽

Absorption Refrigeration ◽

Evaporation Temperature ◽

Corrosion Rates ◽

Specific Entropy

When compared with LiBr/H2O, an absorption refrigeration cycle using CaCl2/H2O as the working pair needs a lower driving heat source temperature, that is, CaCl2/H2O has a better refrigeration characteristic. However, the crystallization temperature of CaCl2/H2O solution is too high and its absorption ability is not high enough to achieve an evaporation temperature of 5 °C or lower. CaCl2-LiNO3-KNO3(15.5:5:1)/H2O was proposed and its crystallization temperature, saturated vapor pressure, density, viscosity, specific heat capacity, specific entropy, and specific enthalpy were measured to retain the refrigeration characteristic of CaCl2/H2O and solve its problems. Under the same conditions, the generation temperature for an absorption refrigeration cycle with CaCl2-LiNO3-KNO3(15.5:5:1)/H2O was 7.0 °C lower than that with LiBr/H2O. Moreover, the cycle’s COP and exergy efficiency with CaCl2-LiNO3-KNO3(15.5:5:1)/H2O were approximately 0.04 and 0.06 higher than those with LiBr/H2O, respectively. The corrosion rates of carbon steel and copper for the proposed working pair were 14.31 μm∙y−1 and 2.04 μm∙y−1 at 80 °C and pH 9.7, respectively, which were low enough for engineering applications.

Download Full-text

Structural and electrical properties of the new sulfosalt Sn2Sb6S11 thin films prepared by vacuum thermal evaporation

Journal of Materials Science Materials in Electronics ◽

10.1007/s10854-015-3422-4 ◽

2015 ◽

Vol 26 (10) ◽

pp. 7763-7770 ◽

Cited By ~ 1

Author(s):

I. Trabelsi ◽

N. Ben Mehrez ◽

M. Kanzari

Keyword(s):

Thin Films ◽

Electrical Properties ◽

Thermal Evaporation ◽

Vacuum Thermal Evaporation ◽

Structural And Electrical Properties

Download Full-text

Лазерно-индуцированные фазовые превращения в стеклообразных пленках Se, полученных вакуумно-термическим испарением

Письма в журнал технической физики ◽

10.21883/pjtf.2018.17.46575.17373 ◽

2018 ◽

Vol 44 (17) ◽

pp. 86

Author(s):

Е.В. Александрович ◽

Е.В. Степанова ◽

К.Г. Михеев ◽

Г.М. Михеев

Keyword(s):

Reflection Coefficient ◽

Laser Irradiation ◽

Room Temperature ◽

Thermal Evaporation ◽

Amorphous Matrix ◽

Nucleation And Growth ◽

Power Laser ◽

Vacuum Thermal Evaporation ◽

Average Size ◽

First Time

AbstractThe results of the study of vitreous Se films obtained by a method of vacuum-thermal evaporation after their laser modification are presented. It is shown for the first time that a low-power laser irradiation of the film at a wavelength of 632.8 nm and room temperature results in a nucleation and growth of nanocrystallites of monoclinic and rhombohedral Se in an amorphous matrix of the film. The formation of the stable hexagonal Se phase is not observed. The appearance of nanocrystallites with an average size of ~20–30 nm is accompanied by a growth of a reflection coefficient of the film. The established new optical and structural properties of the formed films are stable in time at room temperature.

Download Full-text

Твердофазные превращения в наноразмерных пленочных структурах Se/Cu, полученных методом вакуумно-термического испарения

Письма в журнал технической физики ◽

10.21883/pjtf.2020.09.49370.18118 ◽

2020 ◽

Vol 46 (9) ◽

pp. 32

Author(s):

В.Я. Когай ◽

Г.М. Михеев

Keyword(s):

Phase Composition ◽

Phase Transformations ◽

Thermal Evaporation ◽

Solid Phase ◽

Experimental Results ◽

Vacuum Thermal Evaporation ◽

First Time

The experimental results of the study of solid-phase transformations occurring in nanoscale film structures of Se / Cu obtained by vacuum-thermal evaporation are presented. It was shown for the first time that by changing the ratio of copper and selenium atoms (N) in the sample, one can control the phase composition of the synthesized films. A relationship was established between N and the phase composition of the synthesized films.

Download Full-text