What is nano alumina?
Nano-alumina is widely used in various fields such as ceramic materials, composite materials, aerospace, environmental protection, catalysts, and their carriers because of its high strength, hardness, wear resistance, heat resistance, and large specific surface area . This has led to the continuous improvement of its development technology. Currently, scientists have prepared alumina nanomaterials in various morphologies from one-dimensional to three-dimensional, including spherical, hexagonal sheet, cubic, rod, fibrous, mesh, flower, curly, and many other morphologies .
Scanning electron microscopy of alumina nano-particles
There are many methods for the preparation of nano alumina, which can be divided into three main categories according to the different reaction methods:
Solid-phase, gas-phase, and liquid-phase methods . In order to verify that the results of the prepared alumina nanopowders are as expected, it is necessary to characterize the structure of alumina under each process, and the most intuitive of the many characterization methods is the microscopic observation method.
The scanning electron microscope, as a conventional microscopic characterization equipment, has the advantages of large magnification, high resolution, large depth of field, clear imaging, and strong stereoscopic sense, which is the preferred equipment for characterizing the structure of nano-alumina.
The following figure shows the alumina powder prepared under different processes observed using CIQTEK Field Emission Scanning Electron Microscope SEM5000, which contains alumina nanopowders in the form of cubes, flakes, and rods, and with particle sizes of tens to hundreds of nanometers.
CIQTEK Field Emission Scanning Electron Microscope SEM5000
SEM5000 is a high-resolution, feature-rich field emission scanning electron microscope, with advanced barrel design, in-barrel deceleration, and low aberration non-leakage magnetic objective design, to achieve low-voltage high-resolution imaging, that can be applied to magnetic samples. SEM5000 has optical navigation, perfect automatic functions, well-designed human-machine interaction, and optimized operation, and use process. Regardless of whether the operator has extensive experience, he/she can quickly get started with the task of high-resolution photography.
Electron gun type: high-brightness Schottky-field emission electron gun
Resolution: 1 nm @ 15 kV
1.5 nm @ 1 kV
Magnification: 1 ~ 2500000 x
Acceleration voltage: 20 V ~ 30 kV
Sample table: five-axis automatic sample table
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