Characterization and testing technology is the fundamental way to scientifically identify nanomaterials, understand their diverse structures, and evaluate their special properties. The main purpose of characterization of nanomaterials is to determine some physical and chemical properties of nanomaterials, such as morphology, size, particle size, chemical composition, crystal structure, band gap and light absorption properties. The composition characterization of nano-powder usually has the following methods:

1. Atomic absorption spectroscopy (AAS)

The content of the tested element in the sample is determined according to the absorption intensity of its atomic resonance radiation by the ground state atoms of the tested element in the vapor phase.
It is suitable for quantitative determination of trace metal impurities in nanomaterials with low detection limit.
The measurement accuracy is very high.
The selection is good, and no separation detection is required.
A wide range of analytical elements is available.
Refractory elements, rare earth elements and non-metallic elements cannot be simultaneously analyzed for multiple elements.

2. Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP)
ICP is a method that uses inductively coupled plasma as the excitation source to analyze the element to be tested according to the characteristic spectral lines emitted when the atoms of the element to be tested in the excited state return to the ground state.
Simultaneous analysis of multiple elements is possible.
Very low detection limit.
The stability is very good, the precision is very high, and the quantitative analysis effect is good.
The detection sensitivity of non-metallic elements is low.

3. Inductively Coupled Plasma Mass Spectrometry ICP-MS
ICP-MS is an elemental mass spectrometry method using inductively coupled plasma as the ion source.
The detection limit is low.
Analysis is fast.
The spectrum interference is less, and isotope analysis can be carried out.

4. X-ray fluorescence spectroscopy XFS
This is a non-destructive analytical method that can be measured directly on solid samples. It has great advantages in the composition analysis of nanomaterials.
It has good qualitative analysis ability and can analyze all elements with atomic number greater than 3.
High analytical sensitivity.

5. Electron probe analysis EPMA
The method of analyzing according to the wavelength and intensity of X-rays is called electron probe analysis.
The analysis accuracy is high.
High analytical sensitivity.
Non-destructive sample, multi-element simultaneous detection.
Constituency analysis is available.
Electron probe analysis is bad for light elements.

6. X-ray photoelectron spectroscopy (XPS)
XPS is a surface analysis method that uses X-rays to irradiate the sample, so that the inner electrons or valence electrons of atoms or molecules are excited and emitted, and the electrons excited by photons are called photoelectrons, which can measure the energy and quantity of photoelectrons, thereby Obtain the analyte composition.
It is an analysis that mainly measures the binding energy of electrons to identify the chemical properties and composition of the sample surface.
Qualitative and quantitative analysis of elements.
Solid Surface Analysis.
Within 10 nm of the photoelectron from the surface, only the chemical information of the surface is brought out, which has the characteristics of small analysis area, shallow analysis depth and no damage to the sample.