Ferroelectric Multilayer Nanocomposites with Polarization and Stress Concentration Structures for Enhanced Triboelectric Performances

• Published in: ACS nano Vol. 14; no. 6; pp. 7101 - 7110
• Main Authors: Park, Yoojeong, Shin, Young-Eun, Park, Jonghwa, Lee, Youngsu, Kim, Minsoo P, Kim, Young-Ryul, Na, Sangyun, Ghosh, Sujoy Kumar, Ko, Hyunhyub
• Format: Journal Article
• Language: English
• Published: American Chemical Society 23.06.2020
• Subjects: stress concentration; ferroelectric composite; soft/hard multilayer; self-powered sensor; triboelectric sensor
• ISSN: 1936-0851; 1936-086X
• DOI: 10.1021/acsnano.0c01865

Although ferroelectric composites have been reported to enhance the performance of triboelectric (TE) devices, their performances are still limited owing to randomly dispersed particles. Herein, we introduce high-performance TE sensors (TESs) based on ferroelectric multilayer nanocomposites with alternating poly­(vinylidenefluoride-co-trifluoroethylene) (PVDF-TrFE) and BaTiO3 (BTO) nanoparticle (NP) layers. The multilayers comprising alternating soft/hard layers can induce stress concentration and increase the effective stress-induced polarization and interfacial polarization between organic and inorganic materials, leading to a dielectric constant (17.06) that is higher than those of pure PVDF-TrFE films (13.9) and single PVDF-TrFE/BTO nanocomposites (15.9) at 10 kHz. As a result, the multilayered TESs with alternating BTO NP layers exhibit TE currents increased by 2.3 and 1.5 times compared to pure PVDF-TrFE without BTO NPs and PVDF-TrFE/BTO nanocomposites without multilayer structures, respectively. The multilayered TESs exhibit a high pressure sensitivity of 0.94 V/kPa (48.7 nA/kPa) and output power density of 29.4 μWcm–2, enabling their application in the fabrication of highly sensitive healthcare monitoring devices and high-performance acoustic sensors. The suggested architecture of ferroelectric multilayer nanocomposites provides a robust platform for TE devices and self-powered wearable electronics.