Energy-harvesting enhancement in composites of microwave-exfoliated KNN and multiwall carbon nanotubes

Abstract

The objective of this research work is to investigate the effect of multiwall carbon nanotube (MWCNT) content (0.3-1.2 wt%) on a potassium sodium niobate (KNN)-based piezoelectric unimorph harvester for enhancing the energy generation capacity. KNN-MWCNT composites were fabricated by using a microwave solid state technique. The energyharvesting performance of the KNN-MWCNT composite was determined by the base excitation method and sized to resonate between 20 and 100 Hz at 1 M load resistance. The energy performance of the KNN composite at percolation threshold (0.6 wt% MWCNT) showed a maximum power generation of 2.94 µW, the power density of 7.15 µW m −3 and overall efficiency of 83.75% at an input acceleration of 0.5 g and a load resistance of 1 M. Improvements observed in the power generation by percolation phenomena and ionic flow over the nanotube surface of KNN composites prove to be a boon for low-power sensing devices.

Elastic Polarization Configuration Coupled with Activity Rattling Space Boosts Energy Harvesting Performance of Lead‐Free Piezoceramic

“…Additionally, the difficulty involved in regulating the output current density (I out ) represents another bottleneck that prevents the practical application of PEHs. [9][10][11] Because the rated current is required to actuate passive sensors with a given internal resistance, currents that are too high or too low will prevent the passive sensors from working. In summary, designing a PEH system to have a stable V out and a controllable I out to meet the differing energy supply requirements of various passive sensors is of major practical significance.…”