Multi-directional hybrid friction nanogeneration with applying to collect wave kinetic energy

With the growth of global energy demand and the challenges of environmental change, the development of renewable energy has become a key issue. Piezoelectric thin film (PVDF) and triboelectric nanogenerator (TENG) have attracted widespread attention due to their ability to harvest energy from the environment. However, the performance of conventional TENG is often limited by its complex mechanical structure and difficulty in integration into ship systems. To this end, this paper proposes a new multi-directional composite energy harvester with a simple structure that can be effectively integrated into ship systems. The energy harvester is particularly sensitive to low-frequency and irregular excitations and can capture wave energy in multiple directions. In this paper, a six-degree-of-freedom experimental platform is used to simulate the frequency, amplitude, pitch and roll of waves, comprehensively evaluate the performance of TENG under wave conditions, and optimize the cantilever beam thickness, the copper foil area inside the triboelectric nanogenerator, and the friction material of the triboelectric nanogenerator. Finally, a piezoelectric–triboelectric nanogenerator composite wave energy harvester (PE-TENG) is proposed. On this basis, a multilayer piezoelectric–triboelectric nanogenerator (MPE-TENG) is further developed, with an optimal voltage output of 100.53 V, a short-circuit current of 25.67 μA, and a peak power of 514.91 μW. The MPE-TENG successfully drove hundreds of LED lights, verifying its good stability and feasibility as a large-scale blue ocean energy harvesting tool for passenger ships. The optimization process in this paper not only improves the energy conversion efficiency of the system, but also provides a new design idea for wave energy capture in ship applications.