Lead-free silver niobate microparticles-loaded PDMS composite films for high-performance clip-like hybrid mechanical energy harvesters

A triboelectric nanogenerator (TENG) is a highly potential green energy harvesting technology to power small-scale electronic devices. Enhancing the overall electricity production capacity of TENGs is a primary concern for their utilization as an electricity generator in day-to-day life. Herein, we proposed a lead-free silver niobate (AgNbO₃ (ANb)) microparticles (MPs)-embedded polydimethylsiloxane (PDMS) composite film-based clip-like hybrid nanogenerator (HNG) device, producing an enhanced electrical output from the applied mechanical movements. The ANb MPs with a high dielectric constant were initially synthesized and embedded inside the PDMS polymer matrix. Various HNGs were fabricated utilizing ANb MPs/PDMS composite films/aluminum tape as negative/positive triboelectric films, respectively and operated in contact-separation mode. The electrical output from them was comparatively analyzed to investigate an optimum concentration of the ANb MPs inside the PDMS film. The robust HNG with 5 wt % ANb MPs/PDMS composite film produced the highest electrical output with promising stability. Thereafter, three similar optimized HNGs were fabricated and integrated within a 3D-printed clip-like structure and the electrical output was thoroughly evaluated while combining multiple HNGs as well as from each independent HNG. The clip-like HNG device exhibited an electrical output of 340 V and 20 µA that can be further utilized to charge various capacitors and power portable electronics. Owing to the high resilience structure of the clip-like HNG device, it was also demonstrated to harvest biomechanical energy produced by human movements into electricity. The mechanical energy harvesting when the clip-like HNG device was attached to the accelerator pedal of the car and the pedal of a musical piano was successfully demonstrated.