Phase transformation and room temperature stabilization of various Bi2O3 nano-polymorphs: effect of oxygen-vacancy defects and reduced surface energy due to adsorbed carbon species

Nanoscale ◽  
2020 ◽  
Vol 12 (47) ◽  
pp. 24119-24137
Author(s):  
Ashish Chhaganlal Gandhi ◽  
Chi-Yuan Lai ◽  
Kuan-Ting Wu ◽  
P. V. R. K. Ramacharyulu ◽  
Valmiki B. Koli ◽  
...  
Keyword(s):  
Phase Transformation ◽  
Oxygen Vacancy ◽  
Surface Energy ◽  
Room Temperature ◽  
Temperature Stabilization ◽  
Red Emission ◽  
Vacancy Defects ◽  
Adsorbed Carbon ◽  
Effect Of Oxygen ◽  
Reduced Surface

The air annealing induced grain growth from nano to microscale and a transformation sequence from Bi → β-Bi2O3 → γ-Bi2O3 → α-Bi2O3 was evident. All the annealed samples are oxygen-deficient, resulting in the appearance of a strong red emission band.

Tremendous effect of oxygen vacancy defects on the oxidation of arsenite to arsenate on cryptomelane-type manganese oxide

2016 ◽  
Vol 306 ◽  
pp. 597-606 ◽  
Author(s):  
Jingtao Hou ◽  
Jinglin Luo ◽  
Zhongqiu Hu ◽  
Yuanzhi Li ◽  
Mingyang Mao ◽  
...  
Keyword(s):  
Oxygen Vacancy ◽  
Manganese Oxide ◽  
Vacancy Defects ◽  
Effect Of Oxygen

Enhanced room temperature ferromagnetism in electrodeposited Co-doped ZnO nanostructured thin films by controlling the oxygen vacancy defects

2015 ◽  
Vol 117 (21) ◽  
pp. 214310 ◽  
Author(s):  
A. Simimol ◽  
Aji A. Anappara ◽  
S. Greulich-Weber ◽  
Prasanta Chowdhury ◽  
Harish C. Barshilia
Keyword(s):  
Thin Films ◽  
Oxygen Vacancy ◽  
Room Temperature ◽  
Room Temperature Ferromagnetism ◽  
Vacancy Defects ◽  
Nanostructured Thin Films ◽  
Doped Zno ◽  
Co Doped

scholarly journals Aerosol nanoparticles in the Fe1−xCrx system: Room-temperature stabilization of the σ phase and σ→α-phase transformation

2005 ◽  
Vol 98 (2) ◽  
pp. 024303 ◽  
Author(s):  
M. Gich ◽  
E. A. Shafranovsky ◽  
A. Roig ◽  
A. Ślawska-Waniewska ◽  
K. Racka ◽  
...  
Keyword(s):  
Phase Transformation ◽  
Room Temperature ◽  
Temperature Stabilization ◽  
Σ Phase ◽  
Aerosol Nanoparticles ◽  
Α Phase

Flower-like Co3O4 sensor with rich oxygen vacancy defects for enhancing room temperature NOx sensing performances

2021 ◽  
Vol 868 ◽  
pp. 159180
Author(s):  
Huiling Liu ◽  
Hailiu He ◽  
Liqiang Chen ◽  
Qingjiang Pan ◽  
Guo Zhang
Keyword(s):  
Oxygen Vacancy ◽  
Room Temperature ◽  
Vacancy Defects

scholarly journals Structural and Enhanced Optical Properties of Stabilized γ‒Bi2O3 Nanoparticles: Effect of Oxygen Ion Vacancies

Nanomaterials ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 1023 ◽  
Author(s):  
Ashish Chhaganlal Gandhi ◽  
Chia-Liang Cheng ◽  
Sheng Yun Wu
Keyword(s):  
Room Temperature ◽  
Excess Oxygen ◽  
Ambient Atmosphere ◽  
Photoluminescence Spectra ◽  
X Ray Diffraction ◽  
X Ray ◽  
Band Emission ◽  
Oxygen Ion ◽  
Integrated Intensity ◽  
Effect Of Oxygen

We report the synthesis of room temperature (RT) stabilized γ–Bi2O3 nanoparticles (NPs) at the expense of metallic Bi NPs through annealing in an ambient atmosphere. RT stability of the metastable γ–Bi2O3 NPs is confirmed using synchrotron radiation powder X-ray diffraction and Raman spectroscopy. γ–Bi2O3 NPs exhibited a strong red-band emission peaking at ~701 nm, covering 81% integrated intensity of photoluminescence spectra. Our findings suggest that the RT stabilization and enhanced red-band emission of γ‒Bi2O3 is mediated by excess oxygen ion vacancies generated at the octahedral O(2) sites during the annealing process.

scholarly journals Room-temperature oxygen vacancy migration induced reversible phase transformation during the anelastic deformation in CuO

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Lei Li ◽  
Guoxujia Chen ◽  
He Zheng ◽  
Weiwei Meng ◽  
Shuangfeng Jia ◽  
...  
Keyword(s):  
High Temperature ◽  
Oxygen Vacancy ◽  
Room Temperature ◽  
High Temperature Superconductivity ◽  
Experimental Investigations ◽  
Solid State Chemistry ◽  
Vacancy Migration ◽  
Scientific Disciplines ◽  
Anelastic Deformation ◽  
Reversible Phase

AbstractFrom the mechanical perspectives, the influence of point defects is generally considered at high temperature, especially when the creep deformation dominates. Here, we show the stress-induced reversible oxygen vacancy migration in CuO nanowires at room temperature, causing the unanticipated anelastic deformation. The anelastic strain is associated with the nucleation of oxygen-deficient CuOx phase, which gradually transforms back to CuO after stress releasing, leading to the gradual recovery of the nanowire shape. Detailed analysis reveals an oxygen deficient metastable CuOx phase that has been overlooked in the literatures. Both theoretical and experimental investigations faithfully predict the oxygen vacancy diffusion pathways in CuO. Our finding facilitates a better understanding of the complicated mechanical behaviors in materials, which could also be relevant across multiple scientific disciplines, such as high-temperature superconductivity and solid-state chemistry in Cu-O compounds, etc.

Sign in / Sign up

Export Citation Format

Share Document