Nano-Engineered Carbon Fibre-Based Piezoelectric Smart Composites for Energy Harvesting and Self-Powered Sensing

The integration of piezoelectric materials onto carbon fiber (CF) can add energy harvesting and self-power sensing capabilities enabling great potential for Internet of Things (IoT) applications in motion tracking, environmental sensing, and personal portable electronics. Herein, a CF-based smart composite is developed by integrating piezoelectric poly(3,4-ethylenedioxythiophene) (PEDOT)/CuSCN-coated ZnO nanorods onto the CF surfaces with no detrimental effect on the mechanical properties of the composite, forming composites using two different polymer matrices: highly flexible polydimethylsiloxane (PDMS) and more rigid epoxy. The PDMS-coated piezoelectric smart composite can serve as an energy harvester and a self-powered sensor for detecting variations in impact acceleration with increasing output voltage from 1.4 to 7.6 V under impact acceleration from 0.1 to 0.4 m s(-2). Using epoxy as the matrix for a CF-reinforced plastic (CFRP) device with sensing and detection functions produces a voltage varying from 0.27 to 3.53 V when impacted at acceleration from 0.1 to 0.4 m s(-2), with a lower output compared to the PDMS-coated device attributed to the greater stiffness of the matrix. Finally, spatially sensitive detection is demonstrated by positioning two piezoelectric structures at different locations, which can identify the location as well as the level of the impacting force from the fabricated device.

Automated summary

The article introduces a method of integrating piezoelectric materials onto carbon fiber surfaces, which provides energy harvesting and self-powered sensing capabilities for IoT applications. The developed CF-based smart composite, using PEDOT/CuSCN-coated ZnO nanorods integrated onto the CF surfaces, does not affect the mechanical properties of the composite. Two different polymer matrices, highly flexible PDMS and more rigid epoxy, were used to prepare composites. The PDMS-coated piezoelectric smart composite functions as an energy harvester and self-powered sensor, with an output voltage ranging from 1.4 to 7.6 V under impact acceleration from 0.1 to 0.4 m s(-2). The CFRP device with epoxy as the matrix produces a voltage varying from 0.27 to 3.53 V under the same impact acceleration, with lower output due to the stiffness of the matrix. Spatially sensitive detection capability is demonstrated by positioning two piezoelectric structures at different locations, enabling identification of the impacting force's location and level.