Organic solar cell, is composed of organic material core part of the solar cell. Mainly with photosensitive organic matter as a semiconductor material, to photovoltaic effect and generate voltage to form 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 cell has the characteristics of flexibility, light weight, adjustable color, solution processing, large-area printing and so on. It is a hot spot in the research field of solar cell. However, low efficiency is the main reason that restricts its large-scale application.
Second, the structure principle of organic solar cells
1. Principle of organic solar cells
Organic solar cells take photosensitive organic matter as semiconductor material and generate voltage to form current by photovoltaic effect. The main photosensitive organic materials all have conjugated structure and conductivity, such as phthalocyanine compound, porphyrin, cyanine, etc.
2. Several structures of organic solar cells
Organic solar cells can be divided into simple junction structure, P-N heterojunction structure and dye-sensitized nanocrystalline structure according to the semiconductor materials.
3. Simple junction structure
The structure of simple junction is an organic solar cell based on Schotty barrier. Its structure is glass/metal electrode/dye/metal electrode, which makes use of the different power functions of the two electrodes. An electric field can be generated, and electrons are transferred from the metal electrode with low power function to the high power correspondence electrode to generate photocurrent. Since electron-hole transfer in the same material, its photoelectric conversion rate is relatively low.
4. P-n heterojunction structure p-N
Heterojunction structure refers to the structure with donor-acceptor (n-type semiconductor and P-type semiconductor) heterojunction structure. The semiconductor materials are mostly dyes, such as phthalocyanine compounds and perylene tetraformalin imines. The separation efficiency is improved by using the D/A interface between semiconductor layers (Donor, Acceptor, Acceptor) and electron-hole transfer in different materials. Elias Stathatos et al. combined the advantages of inorganic and organic compounds to produce solar cells with a conversion rate of 5% to 6%.
5. NPC(Nanocrystaline photovoltaic cell) dye-sensitized nanocrystals
Dye-sensitized solar cell (DSSC) is a kind of solar cell which takes dye-sensitized TiO2 thin film with multi-space nanostructure as photoanode. It is a solar cell that mimics the principle of chlorophyll photosynthesis in plants. NPC solar cells can choose appropriate REDOX electrolytes to improve the photoelectric efficiency, generally stable at 10%, and nanocrystalline TiO2 is simple to prepare, low cost, considerable life, has a good market prospect.
