By G.P. Thomas
A report in Nano Letters, a journal of the American Chemical Society, has described a first-of-its-kind ‘pyroelectric nanogenerator,’ which operates on the basis of the pyroelectric effect, a phenomenon first explained by the Greek philosopher Theophrastus 2,300 years ago.
Georgia Tech research team comprising Zhong Lin Wang and colleagues has informed that over 50% of the energy produced in the United States every year is wasted as heat, which is released into the environment. Heat can be transformed to electricity utilizing the pyroelectric effect. Certain materials’ molecular structure gets changed when they are subjected to heating and cooling, creating an imbalance of electrons, which in turn produces an electric current.
Wang's team sought to use the pyroelectric effect to develop a nanogenerator that might leverage heat changes in the current world, which utilizes a time-based temperature change to produce electricity. For this purpose, the research team created nanowires using zinc oxide, a material used in paints, electronics, plastics, and even in food. The team demonstrated a device capable of generating electricity during heating and cooling by utilizing short length nanowire array standing on end.
According to the researchers, these nanogenerators are also able to generate power using the temperature changes between day and night. They informed that this new class of nanogenerators lays the foundation for self-powered nanotechnology that collects thermal energy using the time-dependent temperature changes in the environment for applications, including personal microelectronics, medical diagnostics, temperature imaging and wireless sensors.