ABSTRACT
Since lead-based piezoelectric nanogenerators (PENGs) possess serious health risks, environmental problems, proper disposal issues, and biocompatibility concerns, this work presents the fabrication of a flexible piezoelectric nanogenerator utilizing lead-free orthorhombic AlFeO3nanorods for biomechanical energy scavenging to sustainably power electronics. Hydrothermal technique is used to synthesize the AlFeO3nanorods and the PENG was fabricated on Indium tin oxide (ITO) coated Polyethylene terephthalate (PET) flexible film with AlFeO3nanorods interspersed in polydimethylsiloxane (PDMS). transmission electron microscopy proved that the AlFeO3nanoparticles are of nanorods shape. Through x-ray Diffraction, it is validated that AlFeO3nanorods have orthorhombic phase and crystalline structure. A high piezoelectric charge coefficient (d33) of 400 pm V-1is obtained from the piezoelectric force microscopy of AlFeO3nanorods. With optimized concentration of AlFeO3in the polymer matrix, an open circuit voltage (VOC) of 30.5 V, current density (JC) of 0.7888±0.0001µA cm-2and an instantaneous power density of 240.6 mW m-2are obtained under the application of a force of 1.25 kgf. To investigate the nanogenerator's practical utility, the PENG is used for lighting multiple LEDs, charging of a capacitor and as a pedometer via biomechanical energy harvesting. Hence, it can be employed for developing various self-powered wearable electronics such as flexible skin, artificial cutaneous sensors, etc.
