According to local media informs in Japan, for the new generation of "perovskite solar cell" solar cell materials, researchers at the Advanced Science and Technology Research Center of the University of Tokyo have achieved a high conversion efficiency of 20.5% without using rare metals such as rubidium And stable power generation. The study has realized the stability of the crystalline structure by adding more potassium elements present on Earth. Research group in the long-term durability test at the same time, facing Matsushita and other enterprises practical evaluation and discussion.
The so-called perovskite solar cells, is the use of a perovskite crystal structure of this material solar cells. Compared with the current mainstream of silicon solar cells, the manufacturing process is simple, low manufacturing costs. At present, solar cells with a practical conversion efficiency of more than 20% are used, and rare metals such as rubidium and cesium are used to maintain the structural stability.
The University of Tokyo's research team, by adding potassium to maintain the crystalline structure under certain conditions, succeeded in producing defect-free structured power layers without the use of rare metals at all. Since the electron flow is not hindered, the conversion efficiency is improved Power generation stability.
In addition, the research team also confirmed the use of potassium current and voltage changes in the way, can inhibit changes in power generation, "hysteresis." Rubidium and other metals than the inhibition effect is higher, can be more stable power generation. Solar cell due to hysteresis is difficult to determine the correct conversion efficiency, which was a practical issue.
The University of Tokyo study is part of the New Energy and Industrial Technology Development Agency (NEDO) project. The project aims to achieve a conversion efficiency of 25% by 2020 and an efficiency of 95% or more after 10,000 hours of illumination. Therefore, taking into account the practicality and popularity of the future, the use of readily available materials makes a lot of sense. (Ministry of Science and Technology)