Biowaste crab shell-extracted chitin nanofiber-based superior piezoelectric nanogenerator.

Expeditious development of PENGs has been restricted several problems such as toxicity, high cost, and long-life. Herein, we report a biowaste crab shell-extracted chitin nanofiber (CNF) and CNF/poly(vinylidene fluoride) (PVDF)-based biocompatible, biodegradable, low cost, light weight, flexible, highly durable and efficient piezoelectric nanogenerators (PENGs) that enable harvesting of electrical energy from the mechanical energy of a living system. The pure CNF thin film-based piezoelectric nanogenerator (CPENG) shows excellent output performances (open circuit output voltage (V_oc) = 22 V, short circuit current (I_sc) = 0.12 μA) with a high piezoelectric coefficient, d₃₃ = 9.49 pC N⁻¹. The PENG based on CNF/PVDF (PCPEG) also shows very good output characteristics (V_oc = 49 V and I_sc = 1.9 μA). The incorporation of CNF in a PVDF matrix noticeably enhanced the electroactive β-phase nucleation, (F(β)) ∼ 81%, with a superior d₃₃∼ 35.56 pC N⁻¹. The PCPENG is able to charge a 2.2 μF capacitor to 3.6 V within a short time span (20 seconds) and illuminate 22 blue LEDs connected in series. Our as-fabricated PENGs could be suitable for long-life in vivo biomedical energy harvesting devices that can harvest energy from blood flow and heart beats and charge energy storage devices from mechanical energy such as body movements, moving cars, sea waves, air flow, and rain drops. [ABSTRACT FROM AUTHOR]