Better Thermoelectric Material Developed for Lower TemperaturesCategory: Science & Technology
Posted: May 14, 2014 05:47AM
From computers and cars to power plants, a lot of energy can be lost as heat, which is why many are working on ways to capture and convert that heat into something useful. One way to achieve this is with thermoelectric material, which can heat directly to electricity. Researchers at the University of Houston have recently discovered a material that is more efficient than its competitor at temperatures between room temperature and 300 ºC, and it could be invaluable in many applications.
For many systems, waste heat can add up to temperatures as high as 1000 ºC, and from that down to 200 ºC, we have materials that work well and capturing and converting it. At the lower end and still lower though, the efficiency drops off. Since the 1950s bismuth telluride has been used for temperatures between room temperature and 250 ºC, and while it works, it does not work well. The material developed by the Houston researchers though works across the same range of temperatures, but is more efficient and improving as they work on it more. Thermoelectric materials that cover this lower range of temperatures are very much in demand.
Curiously, the material, made of magnesium, silver, and antimony is actually not new to thermoelectric applications and has been studied previously. What the researchers found is that by preparing it in a specific way, mixing the chemicals in a specific order and at certain times, impurities that impaired its performance would not form.
Source: University of Houston