Detailed explanation of the characteristics and structural principles of organic solar cells
Organic solar cells are solar cells that consist of organic materials at the core. It is mainly based on organic materials with photosensitive properties as semiconductor materials, and the photovoltaic effect generates voltage to form a current to achieve the effect of solar power generation.
First, the characteristics of organic solar cells
As a new type of solar cell device, organic solar cells have the characteristics of flexibility, light weight, adjustable color, solution processing, and large-area printing preparation. They are currently a hot spot in the field of solar cell research. But low efficiency is the main reason that limits its large-scale application.
Second, the structural principle of organic solar cells
1. The principle of organic solar cells
Organic solar cells use photosensitive organics as semiconductor materials, and generate voltages to form currents by the photovoltaic effect. The main photosensitive organic materials have conjugated structure and conductivity, such as phthalocyanine compounds, porphyrins, cyanines, etc.
2. Several structures of organic solar cells
Organic solar cells can be divided into single junction structure, P-N heterojunction structure, and dye-sensitized nanocrystalline structure according to semiconductor materials.
3. Single junction structure
The single-junction structure is an organic solar cell made based on the principle of Schottty barrier. Its structure is glass/metal electrode/dye/metal electrode, which uses the different work functions of the two electrodes to generate an electric field. Electrons are transferred from the metal electrode with low work function to the electrode with high work function to generate photocurrent. Since electrons and holes are all transferred in the same material, the photoelectric conversion rate is relatively low.
4. P-N heterojunction structure P-N
The heterojunction structure refers to a heterojunction structure with a donor-acceptor (N-type semiconductor and P-type semiconductor). Among them, semiconductor materials are mostly dyes, such as phthalocyanine compounds and perylene tetraformaldehyde imine compounds, using the D/A interface (Donor—donor, Acceptor—acceptor) and electron-hole separation between semiconductor layers. The transfer characteristics in different materials increase the separation efficiency. Elias Stathatos and others combined the advantages of inorganic and organic compounds to make solar cells with a photoelectric conversion rate of 5% to 6%.
5. NPC (nanocrystaline photovoltaic cell) dye-sensitized nanocrystals
Dye-sensitized solar cell (DSSC) mainly refers to a type of solar cell that uses dye-sensitized porous nanostructured TiO2 film as the photoanode. It is a solar cell that mimics the photosynthesis principle of plant chlorophyll. However, NPC solar cells can choose appropriate redox electrolytes to increase the photoelectric efficiency, which can generally be stabilized at 10%, and nanocrystalline TiO2 is easy to prepare, low in cost, and has a considerable life span, which has a good market prospect.
Posted by Carrie Wong | WSL Solar Co., Ltd.
WSL Solar has been a quality and professional manufacturer of custom solar panels and solar solution provider in China since 2006.