Synthesis of Spinel-Metal-Oxide/Biopolymer Hybrid Nanostructured Materials

2010 ◽  
Vol 114 (41) ◽  
pp. 17574-17579 ◽  
Author(s):  
M. A. Garza-Navarro ◽  
A. Torres-Castro ◽  
D. I. García-Gutiérrez ◽  
L. Ortiz-Rivera ◽  
Y. C. Wang ◽  
...  
Keyword(s):  
Metal Oxide ◽  
Nanostructured Materials

A review of photocatalytic characterization, and environmental cleaning, of metal oxide nanostructured materials

2021 ◽  
Vol 30 ◽  
pp. e00343
Author(s):  
Muhammad Ikram ◽  
Mahak Rashid ◽  
Ali Haider ◽  
Sadia Naz ◽  
Junaid Haider ◽  
...  
Keyword(s):  
Metal Oxide ◽  
Nanostructured Materials ◽  
Environmental Cleaning

scholarly journals Features of obtaining the catalyst for the synthesis of carbon nanotubes

2019 ◽  
Vol 81 (2) ◽  
pp. 261-267 ◽  
Author(s):  
E. A. Burakova ◽  
G. S. Besperstova ◽  
M. A. Neverova ◽  
A. G. Tkachev ◽  
N. V. Orlova ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Thermal Decomposition ◽  
Metal Oxide ◽  
Specific Surface ◽  
Surface Area ◽  
Nanostructured Materials ◽  
Specific Surface Area ◽  
Oxide System ◽  
Decomposition Stage ◽  
Al2o3 Catalyst

In this paper, the features of obtaining a Co-Mo/Al2O3 catalyst to synthesize carbon nanotubes (CNTs) by thermal decomposition were studied. It was revealed that the duration of the pre-catalyst thermal decomposition stage in the process of developing a metal oxide system has a significant impact on its activity in the synthesis of carbon nanostructured materials by chemical vapor deposition (CVD). It was proved that an effective catalyst for CNTs synthesis can be obtained by through thermal decomposition of the pre – catalyst, without calcination of the metal oxide system. The use of the Co-Mo/Al2O3 catalyst, synthesized in such a way, in the CVD process makes it possible to reduce the cost of synthesized CNTs. Using scanning electron microscopy, it was shown that the size of the grains, and specific surface area of the formed Co-Mo/Al2O3 catalyst depend on the thermal treatment conditions of the pre-catalyst. Under the conditions for the implementation of the pre-catalyst thermal decomposition stage (temperature, volume, duration, etc.), it is possible to contro not only the characteristics of the resulting catalyst (specific surface area, efficiency), but also the characteristics of the CNTs (diameter, degree of defectiveness). In the course of experiments, the optimal modes of implementation of the method for obtaining the Co-Mo/Al2O3 catalyst allowed forming a system with a specific surface area of ~ 108 m2/g. The use of the resulting catalyst in the synthesis of nanostructured materials provides a high specific yield of multi-walled CNTs with a diameter of 8-20 nm and a degree of defectiveness of 0.97.

Purpose-built metal oxide nanomaterials. The emergence of a new generation of smart materials

2000 ◽  
Vol 72 (1-2) ◽  
pp. 47-52 ◽  
Author(s):  
Lionel Vayssieres ◽  
Anders Hagfeldt ◽  
Sten Eric Lindquist
Keyword(s):  
Interfacial Tension ◽  
Metal Oxide ◽  
Nanostructured Materials ◽  
Smart Materials ◽  
Aging Process ◽  
Structural Requirements ◽  
Thermodynamic Stabilization ◽  
Metal Oxide Nanomaterials ◽  
Growth And Aging ◽  
New Generation

A new concept has been developed in order to achieve a new generation of smart materials, namely purpose-built materials, modeled and designed to match the physical and structural requirements of their applications. A model based on the thermodynamic monitoring of the nucleation, growth, and aging process of metal oxide by minimization of the interfacial tension, yielding to the thermodynamic stabilization of the system, results in well-designed and well-ordered nanostructured materials with the required porosity, morphology, size, and orientation on various substrates.

Biogenic Synthesis of Metal/Metal Oxide Nanostructured Materials

2021 ◽  
Vol 22 ◽  
Author(s):  
Aniruddha Mondal ◽  
Mayuri S. Umekar ◽  
Ganesh S. Bhusari ◽  
Prashant B. Chouke ◽  
Trimurti Lambat ◽  
...  
Keyword(s):  
Metal Oxide ◽  
Nanostructured Materials ◽  
Scientific Community ◽  
Review Article ◽  
Biogenic Synthesis ◽  
Toxic Emissions ◽  
Naturally Occurring ◽  
Current Review ◽  
Metal Metal ◽  
Synthesis Routes

: Nanotechnology is an emerging outlet of the nanoscience in which the atoms are encompassed in nanoscale dimensions and come to be more receptive compared with their distinctive counterparts. Recently, the utilization of synthetic designs and physicochemical approaches have received special attention; nevertheless, the generation of noxious impressions on the eco-system have raised serious concerns of the scientific community worldwide. Presently, environmentfriendly green synthesis routes are promising venues for the arrangement of metal/metal oxide (M/MO) nanostructured materials by using plants and their corresponding alliances. This revolution is predominantly recompensing as far as the reduction of toxic emissions and wastes is concerned. Accordingly, materials scientists have adopted various renewable naturally occurring eco-friendly materials, and biogenic processes to fabricate the functional M/MO nanostructured materials. The current review article recapitulates and assimilates the present state of knowledge on different strategies for biogenic fabrication of M/MO nanostructured materials. Moreover, their diverse applications are summarized and discussed.

Electronic Structure and Chemistry of Iron-Based Metal Oxide Nanostructured Materials: A NEXAFS Investigation of BiFeO3, Bi2Fe4O9, α-Fe2O3, γ-Fe2O3, and Fe/Fe3O4

2008 ◽  
Vol 112 (28) ◽  
pp. 10359-10369 ◽  
Author(s):  
Tae-Jin Park ◽  
Sharadha Sambasivan ◽  
Daniel A. Fischer ◽  
Won-Sub Yoon ◽  
James A. Misewich ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Metal Oxide ◽  
Nanostructured Materials ◽  
Iron Based

Existence of Cubic ZrO2 at 300°C on Bulk Zirconium

1969 ◽  
Vol 27 ◽  
pp. 166-167
Author(s):  
R.A. Ploc
Keyword(s):  
Metal Oxide ◽  
Metal Substrate ◽  
Preferred Orientation ◽  
Monoclinic Zirconia ◽  
Epitaxial Relationship

The manner in which ZrO2 forms on zirconium at 300°C in air has been discussed in the first reference. In short, monoclinic zirconia nucleates and grows with a preferred orientation relative to the metal substrate. The mode of growth is not well understood since an epitaxial relationship which gives minimum misfit between the zirconium ions in the metal/oxide combination is not realized. The reason may be associated with a thin cubic or tetragonal layer of ZrO2 between the inner oxygen saturated metal and the outer monoclinic zirconia.

High-resolution electron microscopy of nanostructured materials

1995 ◽  
Vol 53 ◽  
pp. 172-173
Author(s):  
M. José-Yacamán
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Grain Boundaries ◽  
Nanostructured Materials ◽  
High Resolution Electron Microscopy ◽  
Hrem Image ◽  
Small Particles ◽  
Resolution Electron ◽  
Nanophase Materials

Electron microscopy is a fundamental tool in materials characterization. In the case of nanostructured materials we are looking for features with a size in the nanometer range. Therefore often the conventional TEM techniques are not enough for characterization of nanophases. High Resolution Electron Microscopy (HREM), is a key technique in order to characterize those materials with a resolution of ~ 1.7A. High resolution studies of metallic nanostructured materials has been also reported in the literature. It is concluded that boundaries in nanophase materials are similar in structure to the regular grain boundaries. That work therefore did not confirm the early hipothesis on the field that grain boundaries in nanostructured materials have a special behavior. We will show in this paper that by a combination of HREM image processing, and image calculations, it is possible to prove that small particles and coalesced grains have a significant surface roughness, as well as large internal strain.

Sign in / Sign up

Export Citation Format

Share Document