Researchers at the University of Pennsylvania in the United States have learned a new understanding of the basic science of charge separation and made it possible to produce cheaper organic solar cells. They propose to improve the design and production of efficient solar cells in the future. The latest research results have been published in Nature Communications magazine. Today, the highest efficiency of organic solar cells is about 10% of laboratory-scale data, which is much lower than inorganic monocrystalline silicon-based designs. One of the challenges in achieving a highly efficient organic battery is the separation of electron-hole pairs consisting of a negatively charged electron and its positively charged holes, which are collectively referred to as excitons. Electrons and holes need to be separated to generate electricity. The way to achieve this is by creating a heterojunction where two different organic semiconductors are adjacent to each other, one of which loses one electron and the other one electron, which splits the original excitons. However, a long-standing problem in this field is how to completely separate electrons and holes to generate currents, making it possible to observe its efficiency in most solar cells. In the past few years, a new perspective has been proposed. That is, depending on the high separation efficiency of the quantum effect, electrons or holes are present at the same time in a wave state in several molecules scattered nearby, so that the charge can be more easily The ground was separated. Researchers at the University of Pennsylvania provided new evidence to support this interpretation and established that nanocrystals (also known as fullerenes or buckyballs), a common receptor material composed of C60 molecules, are responsible for the delocalization effect. The essential. This crystal structure is critical to the effective photocurrent generation of organic solar cells. The researchers pointed out that the general view is that this requires a lot of excess energy splitting excitons, which means that there must be a large energy gap between the donor and acceptor materials. However, such a large energy offset will reduce the voltage of the solar cell. The work of the researchers is based on the effect of the delocalization and local crystallinity of the wave function on the charge separation process, eliminating this shift. This result can help people design new molecules and optimize donor and acceptor morphology, helping to increase the voltage of solar cells. The team used a variety of luminescent and electro-absorption spectroscopy techniques along with X-ray diffraction to arrive at a conclusion. Their findings have helped other research teams better understand the charge separation and help design and simulate more efficient organic solar cells. Temporary Fence,Pvc Portable Fence,Pvc Temporary Fence,Security Construction Fence HeBei Bosen Metal Products Co.,Ltd , https://www.hbbosenfence.com
Photo: Nanoscale fullerene molecules on organic solar cells