TU-TESL

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According to foreign media reports, researchers found that in solar energy, organic molecular mixtures can be used to absorb sunlight and convert it into electricity. In addition, this kind of battery can also be used in automobile body and other curved surfaces. This discovery challenges the traditional concept and helps to realize the commercialization of solar cells at an early date. In basic organic solar cells, organic semiconductor films are sandwiched between two electrodes. The film extracts the charge generated in the organic semiconductor layer into an external circuit. For a long time, it has been considered that the electrode surface needs to be 100% conductive to extract the maximum charge. Scientists at the University of Warwick in the UK have found that in organic solar cells, as long as 1% of the surface area of the electrode is conductive, it can fully play its role. Therefore, a series of composite materials can be used at the interface between the electrode and the light trapping organic semiconductor layer to improve the device performance and reduce the cost. Ross Hatton, chief researcher of the Department of chemistry, said: "it is generally believed that to optimize the performance of organic solar cells, the interface between electrodes and organic semiconductors needs to be maximized. We question that. " In order to find out the answer, the researchers developed an electrode model to systematically transform the surface. It can be seen that even if 99% of the electrode surface is insulated, as long as the conductive area is not far away, its performance is the same as that when the surface is 100% conductive. In high performance organic solar cells, an additional transparent layer is arranged at the interface between the electrode and the light collecting organic semiconductor layer. These transparent layers are essential to optimize the light distribution and improve the stability of the device. Of course, the premise is that the charge must be transferred to the electrode. This is a difficult task, because there are not many materials that can meet all the requirements at the same time. "From the new findings, it can be seen that the composite materials of insulator and conductive nanoparticles have great application potential in this field, such as carbon nanotubes, graphene fragments or metal nanoparticles," explained dinesha dabera, a postdoctoral researcher. These materials help to improve equipment performance and reduce costs. At present, organic solar cells are very close to but not fully commercialized, so any technology that can further reduce costs and improve performance will help to achieve this goal. " Organic solar cells do not contain toxic elements and can be processed by roll to roll deposition at low temperature. Therefore, the battery is more environmentally friendly, not only has a very low carbon footprint, but also has a short energy recovery time. "All we have to do is demonstrate the design of solar cells, provide a wider range of material options, and drive commercialization," Hatton said "At present, the demand for solar cells is growing rapidly," Hatton said. The battery can be installed on a light, toneable flexible substrate. Traditional silicon solar cells are very suitable for large-scale power generation on the roof of solar farms and buildings. However, they are difficult to meet the needs of electric vehicles and integrate into the windows of buildings, which are no longer niche applications. Organic solar cells can be installed on these surfaces, and they are very light and do not occupy space. This discovery may promote the development of new flexible solar cells and provide designers with more material options to achieve commercial applications. "