TU-TESL

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According to foreign media reports, Tokyo Metropolitan University Scientists at the University, which will change the name of the university to Tokyo Metropolitan University from April 2020, have used aligned "metal" carbon nanotubes as a device (thermoelectric device), which can convert heat energy into electricity, and the output power is higher than that of devices made of pure semiconductor carbon nanotubes (CNTs) in random networks. This new device does not need to rebalance the conductivity and voltage of semiconductors, which is much better than similar products, and the high-power thermoelectric device can pave the way for more effective utilization of waste heat. (photo source: Capital University, Tokyo) thermoelectric devices can directly convert heat energy into electric energy. In daily life, the exhaust gas of air conditioning, automobile engine and even the heat of the body are usually wasted. If such energy can be recovered and utilized, it will be revolutionary and promote the development of wearable electronic equipment and optoelectronic equipment to a certain extent, They are worn on the skin and powered by body temperature, such as body heat lamps and smart watches. When the temperature gradient (with temperature difference) is formed, the output power of the thermoelectric device will be affected by the conductivity and Seebeck coefficient of the device. The problem is that there is a relationship between Seebeck coefficient and conductivity. When the conductivity of the device increases, the Seebeck coefficient will decrease. In order to generate more energy, these two aspects need to be improved. Semiconductor materials are generally considered the best choice for high-performance thermoelectric devices, but a team led by Professor Kazuhiro Yanagi of Capital University in Tokyo chose "metal" CNT. Unlike pure semiconductor CNT, the conductivity and Sebek coefficient of metal CNT can be enhanced at the same time, thus breaking the relationship between the two. The team further demonstrated that this unique characteristic is due to the one-dimensional metal electronic structure of the material. In addition, the researchers were able to adjust the direction of the metal CNT, and the output power was 5 times of that of the randomly oriented pure semiconductor CNT. High performance thermoelectric components can not only make people use body temperature to provide power for smart phones, but also can be used in biomedicine, and play an important role in daily life in the future.