(Georgia Institute of Technology, 2009-12)
Mason, Celeste
Piezoelectric nanogenerators were created using two designs: coating carbon nanotubes (CNTs) grown on a silicon wafer substrate with a thin film of zinc oxide (ZnO), coupled with an additional gold-coated CNT grown wafer to act as an electrodes and coating carbon nanotubes (CNTs) grown on carbon fiber with each type of coating to form flexible electrodes. The CNTs on all samples were grown using a standard recipe, with thermally evaporated iron as catalyst. ZnO deposition techniques such as RF sputtering and ion-assisted deposition were used. Gold deposition was accomplished by thermal evaporation and RF sputtering. Once electrodes were combined, preliminary electrical testing resulted in measurement of current densities of up to 4.2x10-7 A/cm3. Additional electrical measurements indicated that the current generated was the result of piezoelectric behavior of the ZnO coating. These values may be increased with better penetration of both gold and ZnO coatings during deposition on the CNTs. Improvement of film quality, such as gold adhesion and ZnO crystal orientation, may also increase current generation.