Synthesis, field-emission and electric properties of metastable phase VO2 (A) ultra-long nanobelts

Abstract

High quality single crystalline metastable phase VO(2) (A) ultra-long nanobelts were synthesized by hydrothermal method using inorganic V(2)O(5) sol as precursor and polyethylene glycol (PEG) as both surfactant and reducing agent. It was found that the oriented attach growth mechanism is responsible for the formation of VO(2) (A) nanobelts. In addition to an endothermic peak, an unusual exothermic peak was detected in DSC curve of the nanobelts. The temperature dependence of the lattice parameters have been studied, and it was found that the a-axis expands while the c-axis contracts in the high-temperature XRD test. The VO(2) (A) nanobelt has a low turn-on field of 3.8 V μm(-1) and a high field enhancement factor of 1739 in the field emission measurement. Electrical transport measurement of a single VO(2) (A) nanobelt gives a relative low hoping activation energy of 0.28 eV.

Preparation, Characterization and Thermo-Chromic Properties of EVA/VO2 Laminate Films for Smart Window Applications and Energy Efficiency in Building

“…However, by increasing the concentration of the dopant, SEM images of V 0.99 W 0.01 O 2 and V 0.98 W 0.02 O 2 shows the presence of a rod-like structure. This was attributed to the presence of VO 2 (A) by-product [26,31,32,33]. The above result is in a good agreement with the XRD results, indicated that the presence of VO 2 (A) by-product became more apparent at the high concentration of W dopant.…”

Structural transition and temperature-driven conductivity switching of single crystalline VO2(A) nanowires

“…As a consequence, VO 2 (M) has been recently extensively studied with the aim of developing novel sensors and switching devices. [13][14][15][16] The studies showed that VO 2 (A) undergoes a reversible structural phase transition at around 435 K and is probably used as cathode, electron emission, and optical switch materials. [8][9][10] Nevertheless, presently VO 2 (A) has been received much less attention compared with VO 2 (M), although a comprehensive study of VO 2 (A) phase transition is scientically important to understand the exact physical mechanism of the rst-order structural phase transition which has been debated for decades.…”

“…[8][9][10] Nevertheless, presently VO 2 (A) has been received much less attention compared with VO 2 (M), although a comprehensive study of VO 2 (A) phase transition is scientically important to understand the exact physical mechanism of the rst-order structural phase transition which has been debated for decades. Li et al 16 investigated the electrical transport properties of an individual nanobelt and calculated the low-temperature phase activation energy, but there is no result in A H . It was decades later then Oka et al 10 investigated the crystal structure and transition mechanism of VO 2 (A).…”

Synthesis and formation mechanism of VO2(A) nanoplates with intrinsic peroxidase-like activity

“…23 Li and coworkers reported the ultra-long VO 2 (A) nanobelts synthesized hydrothermally using V 2 O 5 sol as precursor and polyethylene glycol as both surfactant and reducing agent. 24 Xie et al reported the large-scale fabrication of VO 2 (A) nanobelts by simple hydrolysis of VO(acac) 2 and observed an intermediate phase VO 2 (B). 25 In addition, Dai et al prepared 1D VO 2 (A) nanostructures via a one-step hydrothermal method using VOSO 4 and NH 3 $H 2 O as precursors; the prepared material was used as a high performance cathode in LIBs.…”