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

• Published in: Bulletin of materials science 2019-10, Vol.42 (5), p.253, Article 253
• Main Authors: Nadar, Nandini R, Krishna, M, Suresh, A V
• Format: Article
• Language: English
• Subjects: Ceramics; Chemistry and Materials Science; Composite materials; Efficiency; Electric power generation; Energy; Energy harvesting; Engineering; Load resistance; Materials Science; Maximum power; Multi wall carbon nanotubes; Percolation; Performance evaluation; Phase transitions; Piezoelectricity; Power management; Sensors
• ISSN: 0250-4707; 0973-7669
• DOI: 10.1007/s12034-019-1938-6

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 energy-harvesting 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 Ω load resistance. The energy performance of the KNN composite at percolation threshold (0.6 wt% MWCNT) showed a maximum power generation of 2.94 μ W , the power density of 7.15 μ W m - 3 and overall efficiency of 83.75% at an input acceleration of 0.5 g and a load resistance of 1 M Ω . 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. Graphic abstract