Preparation and investigation of sputtered vanadium dioxide films with large phase-transition hysteresis loops

2013 ◽  
Vol 277 ◽  
pp. 218-222 ◽  
Author(s):  
Huafu Zhang ◽  
Zhiming Wu ◽  
Qiong He ◽  
Yadong Jiang
Keyword(s):  
Phase Transition ◽  
Vanadium Dioxide ◽  
Hysteresis Loops ◽  
Large Phase

Structural Phase Transition of Tungsten-Doped Vanadium Dioxide Nanopowders Prepared by Thermolysis

2008 ◽  
Vol 8 (3) ◽  
pp. 1417-1421 ◽  
Author(s):  
Zifei Peng ◽  
Wei Jiang ◽  
Heng Liu
Keyword(s):  
Phase Transition ◽  
Differential Scanning Calorimetry ◽  
Transition Temperature ◽  
Vanadium Dioxide ◽  
Structural Phase ◽  
Hysteresis Loops ◽  
Tungstic Acid ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Transmission Electron

Tungsten-doped vanadium dioxide (VO2) nanopowders were prepared by thermolysis of (NH4)5[(VO)6(CO3)4(OH)9] · 10H2O at low temperature, with active white powdery tungstic acid used as a substitutional dopant. The composition and microstructure of the powders were examined by X-ray diffraction, transmission electron microscope, and differential scanning calorimetry. The change in electrical resistance due to the S–M transition was measured from 0 to 150 °C by the four-probe method. Hysteresis loops and differential scanning calorimetry analysis of the samples indicated that the phase-transition temperature of VO2 nanopowders was 67.15 °C. For tungstendoped VO2 nanopowders, the temperature was reduced to 26.46 °C. After sintering the nanopowders, Tc rose from 26.46 °C to 34.85 °C with the sizes increasing to the bulk. A significant direct correlation between particle size and Tc was confirmed. The results indicated that white powdery tungstic acid is exceptionally effective as a dopant for reducing transition temperature.

scholarly journals Диэлектрическая спектроскопия и особенности механизма фазового перехода полупроводник-металл в пленках VO-=SUB=-2-=/SUB=-

2020 ◽  
Vol 54 (2) ◽  
pp. 153
Author(s):  
А.В. Ильинский ◽  
Р.А. Кастро ◽  
М.Э. Пашкевич ◽  
Е.Б. Шадрин
Keyword(s):  
Phase Transition ◽  
Electrical Properties ◽  
Vanadium Dioxide ◽  
Thermal Hysteresis ◽  
Hysteresis Loops ◽  
Electrical Circuit ◽  
Equivalent Electrical Circuit ◽  
Transition Mechanism ◽  
Metal Phase Transition ◽  
Frequency Dependences

Abstract In the range of 0.1–10^6 Hz, the temperature-induced transformation of the frequency dependences of the dielectric-loss tangent tanδ( f ) as well as the Cole–Cole diagrams for undoped vanadium-dioxide films are investigated. The measurements are carried out in the temperature range T = 273–373 K. It is shown that the shape of the Cole–Cole diagrams for all films depends slightly on the temperature in the specified interval, while the frequencies f _0 corresponding to the peaks of the function tanδ( f ) increase with temperature. The thermal-hysteresis loops of the frequency positions f _0( T ) of the peaks are measured. When interpreting the data of dielectric spectroscopy, a complex equivalent electrical circuit of the sample is used; it makes it possible to detect the presence of two types of grains with different electrical properties in undoped VO_2 films. The presence of two types of grains determines the features of the semiconductor–metal phase-transition mechanism in VO_2 films.

Optical Switching of Coherent VO2 Precipitates Embedded in Sapphire

1995 ◽  
Vol 396 ◽  
Author(s):  
L. A. Gea ◽  
L. A. Boatner ◽  
J. D. Budai ◽  
R. A. Zuhr
Keyword(s):  
Phase Transition ◽  
Vanadium Dioxide ◽  
Thermal Processing ◽  
Optical Switching ◽  
Optical Transmission ◽  
Structural Phase ◽  
Switching Behavior ◽  
New Type ◽  
Single Crystal Sapphire ◽  
Smart Surface

AbstractIn this work, we report the formation of a new type of active or “smart” surface that is produced by ion implantation and thermal processing. By co-implanting vanadium and oxygen into a single-crystal sapphire substrate and annealing the system under appropriate conditions, it was possible to form buried precipitates of vanadium dioxide that were crystallographically oriented with respect to the host AI2O3 lattice. The implanted VO2 precipitate system undergoes a structural phase transition that is accompanied by large variations in the optical transmission which are comparable to those observed for thin films of VO2 deposited on sapphire. Co-implantation with oxygen was found to be necessary to ensure good optical switching behavior.

scholarly journals Phase management in single-crystalline vanadium dioxide beams

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Run Shi ◽  
Yong Chen ◽  
Xiangbin Cai ◽  
Qing Lian ◽  
Zhuoqiong Zhang ◽  
...  
Keyword(s):  
Phase Transition ◽  
Vanadium Dioxide ◽  
Temperature Phase ◽  
Metal Insulator ◽  
Single Crystalline ◽  
Submicron Scale ◽  
Engineering Strategy ◽  
Improved Performance ◽  
Effective Phase ◽  
Two Sides

AbstractA systematic study of various metal-insulator transition (MIT) associated phases of VO2, including metallic R phase and insulating phases (T, M1, M2), is required to uncover the physics of MIT and trigger their promising applications. Here, through an oxide inhibitor-assisted stoichiometry engineering, we show that all the insulating phases can be selectively stabilized in single-crystalline VO2 beams at room temperature. The stoichiometry engineering strategy also provides precise spatial control of the phase configurations in as-grown VO2 beams at the submicron-scale, introducing a fresh concept of phase transition route devices. For instance, the combination of different phase transition routes at the two sides of VO2 beams gives birth to a family of single-crystalline VO2 actuators with highly improved performance and functional diversity. This work provides a substantial understanding of the stoichiometry-temperature phase diagram and a stoichiometry engineering strategy for the effective phase management of VO2.

In Situ Triggering and Dynamically Tracking the Phase Transition in Vanadium Dioxide

2014 ◽  
Vol 118 (29) ◽  
pp. 16279-16283 ◽  
Author(s):  
Ming Li ◽  
Dengbing Li ◽  
Jing Pan ◽  
Hao Wu ◽  
Li Zhong ◽  
...  
Keyword(s):  
Phase Transition ◽  
Vanadium Dioxide

scholarly journals Mg/W-codoped vanadium dioxide thin films with enhanced visible transmittance and low phase transition temperature

2015 ◽  
Vol 3 (26) ◽  
pp. 6771-6777 ◽  
Author(s):  
Ning Wang ◽  
Shiyu Liu ◽  
X. T. Zeng ◽  
Shlomo Magdassi ◽  
Yi Long
Keyword(s):  
Thin Films ◽  
Phase Transition ◽  
Transition Temperature ◽  
Charge Carrier ◽  
Band Gap ◽  
Phase Transition Temperature ◽  
Vanadium Dioxide ◽  
Visible Transmittance ◽  
Vanadium Dioxide Thin Films

Mg2+ and W6+ cations were first codoped into the VO2 lattice, resulting in a widened photon band gap and h+/e− charge carrier accumulation. These effects enhanced the thermochromic performance with a high visible transmission (∼80%) and a low phase transition temperature (∼30 °C).

scholarly journals Recent progress in the phase-transition mechanism and modulation of vanadium dioxide materials

2018 ◽  
Vol 10 (7) ◽  
pp. 581-605 ◽  
Author(s):  
Zewei Shao ◽  
Xun Cao ◽  
Hongjie Luo ◽  
Ping Jin
Keyword(s):  
Phase Transition ◽  
Vanadium Dioxide ◽  
Recent Progress ◽  
Transition Mechanism
Sign in / Sign up

Export Citation Format

Share Document