Science and technology
Research progress of solar dyes that can generate electricity at a glanceThe manufacturing process of solar panel is complicated. After pulling bars and chip slices in the furnace, dark blue solar cells will be produced with acid solution and high temperature. However, with the development of organic solar technology, it may be possible to generate electricity from any object in the future by coating a layer of solar cell "paint". The price of solar energy has dropped by 99% in the past 40 years, but the new solar paint is expected to change the market again. Wai Lun Chan, an associate professor of physics and astronomy at the University of Kansas, said that if the solar coating is successfully developed, there is no need to use expensive equipment to make solar cells, further reducing the cost of solar technology. In the past, many teams have also started to study solar cell coatings. For example, in 2013, buffalo University in the United States and Royal University of technology in Melbourne in Australia launched relevant achievements in 2017, but they all stopped because the batteries were difficult to absorb light. Australian researchers also said that solar coating is a product that will not be available in five years. So how to break through the dilemma? Generally, crystalline silicon solar energy is a multi-layer structure, which is composed of upper and lower electrodes and p-type and n-type semiconductors. When the semiconductors absorb the sunlight, the PN junction will produce an electron hole pair. The positive hole and the negative electron will move to the p-type semiconductor and n-type semiconductors respectively, and then generate current and voltage. In the design of organic solar energy, the active layer is made up of two organic materials, the donor and the acceptor. The electrode and the semiconductor will also dissolve into a liquid state. It needs to be layered before wiring to generate electricity. In addition, the electrons inside the organic material will not move. Therefore, many electrons lack a pair of "electric holes". According to the latest research by the Kansas University team, they found that the atomic layer of 2D semiconductor molybdenum disulfide can generate multiple free electrons, which are not affected by the lack of electric holes, can generate directional motion under the action of external electric field, and then generate current. According to the team's research published in Journal of American Chemical Society, solar cells that can be made by printing or even special coating have been developed. In addition, materials are not only cheap, but also easy to manufacture. Chan pointed out that in the future, scientists may be able to use this concept to create solar technology that can be used for painting. However, there is still a lot of room for progress in organic solar paint. At present, the team has not published the conversion efficiency or related prototypes, and the highest conversion efficiency of other laboratories is only 15%. There are more durability, stability and other problems. However, if the research and development of solar dye is successful, the original organic solar energy with the advantages of light, low cost, easy recovery and flexibility will add new combat power.