What is the difference between mono and multi? What is the difference between mono and multi?

First, the composition is different.

1. Single crystal: the particles inside the crystal are in three-dimensional space.

It is arranged regularly and periodically, or the whole crystal is composed of the same spatial lattice in the three-dimensional direction, and the arrangement of the particles in the whole crystal in space is long-range order.

2. Polycrystalline: It is a collection of single crystals with many oriented grains.

Second, the characteristics are different.

1. Monocrystalline: a certain shape, long-range orderly. Such as single crystal of copper, single crystal of silicon, etc. Many monocrystalline particles with different orientations and opportunities can be cobbled together into polycrystals. Single crystals are anisotropic.

Target. 2. Polycrystalline: Polycrystalline is isotropic.

Target. Polycrystalline samples are also characteristic when ingesting polycrystalline diffraction patterns or performing diffraction counts.

Third, the nature is different.

1. Single crystal: the macroscopic properties of each part of the crystal are the same; There are different physical properties in different directions in crystals.

Crystals have a periodic structure, and when melted, all parts require the same temperature; Crystals grown in an ideal environment should be convex polygons.

2. Polycrystalline: When the grain size is small in polycrystalline, it is difficult for the grain to visually present the crystal plane.

Crystal prism and other images, the clarity of the sample is poor, and it is scattered light.

The production and manufacturing process of monocrystalline and polycrystalline is different, and the composition is also different, but the final finished product (solar panel) is almost the same, the difference between the two before is that the photoelectric conversion rate is different, monocrystalline has always been higher than polycrystalline conversion efficiency, even in the laboratory is still the case, in addition, the material of monocrystalline is better than polycrystalline, and it is not easy to be damaged in the production process, and in addition, in terms of appearance, monocrystalline is generally monochrome (conventional is blue and black. Foreign countries are basically blue, and most of the domestic surfaces are blue, but the color will become black after lamination, and the polycrystalline colors are very mixed, and there are monochrome blues.

The atoms of a crystal maintain an orderly and repeating structure in three-dimensional space over a long range, and the repeating units of a group of atoms are called unit cells. If the unit cells are neatly and repeatedly arranged in the three-dimensional direction, it is called a single crystal, such as a neatly arranged brick piece by piece. If the unit cells are not arranged in a regular and orderly manner, they are called polycrystalline, such as a pile of chaotic bricks.

What is seen in the microstructure of the material should be the particles, not the grains. The size of the grains is generally in the range of a few to tens of nanometers. If you see it with SEM it will definitely be a particle, if it is TEM it may be a grain.

1. The spatial structure is different

1) A single crystal is a whole crystal composed of a single grain, or can be used with a spatial lattice pattern to run through the entire crystal. Single-crystal samples contain molecules (atoms or ions) in three-dimensional space.

It is a state of solids that is arranged in a regular, periodic manner.

2) Polycrystals are composed of many small grains arranged in the same way but in different directions. For example: commonly used metals. Polycrystals consist of a large number of grains in a single crystal, or cannot be covered by a spatial lattice pattern.

2. The crystal characteristics are different

1) Single crystal has a certain geometric shape; has a fixed melting point; There is anisotropy.

features: 2) Polycrystals have a certain geometric external shape; There is a fixed melting point, and polycrystals are isotropic.

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Crystal characteristics: 1) The crystals formed by the condensation of self-differential acacia and without external interference have neat and regular geometric shapes, that is, the self-normity of the crystals.

2) The crystal has a fixed melting point, and the temperature crystallinity remains constant during the melting process.

3) Single crystals are anisotropic.

4) Crystals can cause regular diffraction of X-rays.

Whether X-ray diffraction can be produced on a macroscopic scale is the main method for determining whether a substance is a crystal or not.

5) The crystal plane corresponding to the crystal.

The angles are equal and are called conservation of crystal plane angles.

Single crystal. Solid substances are divided into crystalline and amorphous. Crystals are divided into single crystals, polycrystals.

A single crystal is a molecule (atom or ion) contained in a sample in three-dimensional space.

It is a state of solids that is arranged in a regular, periodic manner. The drug substance (usually consisting of a single component) in a chemical drug is recrystallized in a suitable solvent system.

Suitable for X-ray diffraction can be obtained.

The size of the single crystal sample used is about 05 mm. For example: snowflakes, small particles of table salt, etc. Single crystal is an important material in semiconductor science and technology.

Crystal: Crystals have three characteristics: (1) crystals have a certain geometric shape; (2) The crystal has a fixed melting point; (3) Crystals are anisotropic.

features: A single crystal is a crystal with the same atomic arrangement and the same lattice position. For example: monocrystalline silicon.

Polycrystalline is composed of many small grains with the same arrangement but inconsistent orientation, and is called polycrystalline. For example: commonly used metals.

A single crystal has three characteristics of a crystal.

Polycrystals have the first two characteristics but are isotropic.

features: Polycrystalline.

The whole object is made up of many small crystals arranged in a haphazard manner, and such an object is called polycrystalline. For example: commonly used metals. The atoms are not arranged according to uniform rules throughout the crystal, there is no definite shape, and their physical properties are the same in all directions.

For example, table salt is made up of many single crystals of table salt stuck together to form large chunks.

Polycrystals have a definite melting point.

The components are different.

The so-called monocrystal, monocrystalline, single crystal, that is, the particles inside the crystal are arranged regularly and periodically in three-dimensional space, or the whole crystal is composed of the same spatial lattice in the three-dimensional direction, and the arrangement of particles in the whole crystal in space is long-range order. The entire lattice of a single crystal is continuous, which has important industrial applications.

Due to entropy effects that lead to suboptimal microstructures of solids, such as impurities, uneven strains, and crystal defects, ideal single crystals of a certain size are extremely rare in nature and are also difficult to produce in the laboratory. On the other hand, in nature, undesirable single crystals can be very huge, for example some minerals such as emeralds, gypsum, feldspar are known to form crystals up to several meters.

A double crystal is equivalent to two single crystals growing together, so there will be an intergrain boundary (grain boundary) in the middle

Therefore, the difference between the two is that the dual crystal is more than the single crystal interface.

Their atomic arrangements are different

What is Twin? I only know poly ...

There is a difference, the initial raw materials of monocrystalline cells and polycrystalline cells are both primary polysilicon, similar to the existence of a microcrystalline state. To be able to generate electricity, it is necessary to make crystalline silicon from the microcrystalline state of silicon, and the crystal orientation of the crystalline silicon needs to be precisely controlled. The only thing that monocrystalline and polycrystalline cells are not easily interchangeable in the process is crystal growth.

In this process, the primary polysilicon is produced in a monocrystalline furnace into monocrystalline silicon rods with a single crystal orientation, no grain boundaries, dislocation defects and very low impurity densities.

The growth process of polycrystalline crystal itself determines that it cannot grow crystals (single crystals) with a large area of single crystal orientation, and the essence of polycrystalline is the aggregate of a large number of small single crystals.

The differences between monocrystalline and polycrystalline and the basis for judgment are as follows:

1. Differences in appearance:

From the appearance, the four corners of the monocrystalline silicon cell are arc-shaped, and there is no pattern on the surface; The four corners of the polycrystalline silicon cell are square corners, and the surface has a pattern similar to that of an ice flower. Hidden disturbances.

2. Use the above differences:

For users, there is not much difference between monocrystalline silicon cells and polycrystalline silicon cells, and their life and stability are very good. The average conversion efficiency of monocrystalline silicon cells is higher than that of polycrystalline silicon, but it is currently higher than that of polycrystalline.

3. Manufacturing process:

Polycrystalline cells have fewer production process steps than monocrystalline cells, so the energy consumed in the manufacturing process of polycrystalline silicon solar cells is slightly less than that of monocrystalline silicon solar cells, but the power generation of monocrystalline cell modules is higher, and the energy consumption ratio is not much different in the overall calculation.

The role of photovoltaic power generation cells:

Solar photovoltaic cells are the core materials of solar photovoltaic modules. It is used to seal the edge of the solar frame and junction box of the solar panel. The spill trough, like the solar frame notch, is designed to prevent the silicone from spilling. <>