Comparative Study of Energy Harvesting from ZnO Nanorods Using Different Flexible Substrates

The step toward the fabrication of nanodevices with low cost and improved performance is of high demand; therefore, in the present study, different flexible substrates like common paper, textile fabric, plastic and aluminum foil have been utilized to harvest electrical energy. ZnO nanorods (NRs) were grown by using low temperature aqueous chemical growth method. The obtained ZnO NRs were highly dense, well aligned, uniformly distributed over the substrates and exhibited good crystal quality. The structural study was carried out by using X-ray powder diffraction and scanning electron microscopy. The piezoelectric properties of ZnO NRs were investigated by the help of an atomic force microscope using contact mode. The measurements of generated piezoelectricity were around 16.2 mV, 23.2 mV, 38.5 mV and 43.3 mV for common paper, textile fabric, plastic and aluminum foil, respectively. This investigation is an important step in order to study the effect of different substrates influencing the magnitude of the output voltage under identical growth and measurement conditions. We expect that this study will help identify the most suitable flexible substrate for harvesting energy. It also offers a promising alternative powering source for the next generation nanodevices using non-conventional substrates like aluminum foil. Moreover, the use of aluminum foil as flexible and low cost substrate may pave the way to develop devices in different fields including energy harvesting.