In the future, the Georgia Tech group hopes to capitalise on this new ’piezophototronic effect’ and further improve the efficiency of their solar cells. Xudong Wang, an expert in piezoelectric nanodevices from the University of Wisconsin-Madison, US, says that he doesn’t think this effect will be used commercially yet as it is such a new discovery, but says: ’I do think this effect can have significant impact on the improvements of photovoltage devices.’ Wang explains: ’The inner-crystal piezopotential tunes the carrier separations and transport processes, which we call the piezo-phototronic effect.’ This is exciting because the output voltage of the solar cell as a whole can be controlled by changing the piezoelectric potential. The team discovered that piezoelectric materials change the electronic band structure inside the device, and this affects the carrier generation, separation and transport at the junction. Solar cells of the p-n junction or metal-semiconductor type use the energy from inbound photons to separate electron-hole pairs that then allow the conduction of electric charge. Inside the gas lighter, a piezo-electric crystal is placed, at. Now, Wang has found an explanation by showing how a simplified ZnO piezoelectric p-n junction solar cell works. The gas lighter works on the principle of the piezo-electric effect (conversion of mechanical stress into electric signal). In a previous investigation, Zhong Lin Wang and his team at the Georgia Institute of Technology, Atlanta, found that putting a piezoelectric semiconductor into a solar cell improved its efficiency but they could not explain why.
Piezo electric lighter code#
The colour code represents the distribution of the piezopotential at the n-type semiconductor
Schematics and energy band diagram of the piezoelectric solar cells under (b) compressive strain and (c) tensile strain, where the polarity and magnitude of the piezopotential can effectively control the carrier generation, separation and transport characteristics. Schematic and energy band diagram of (a) a general nanowire piezoelectric solar cell fabricated using a p-n junction structure.
0 kommentar(er)
