This study proposes and develops a hybrid type of Nanogenerators (NG) with unimorph-based piezoelectric nanogenerator (PENG) and folded triboelectric nanogenerator (TENG) called hybrid PENG- TENG. Firstly, vibration tests were conducted to investigate PENG- TENG's fundamental characteristics under several conditions: the initial distance between materials, vibration frequency, and amplitude. We used some key parameters, such as aspect ratio, connection setup between hybrid devices, and initial distance, to obtain high electric performance and high efficiency. We found that both PENG-TENG were able to complement each other to generate output voltage, and both vibration frequency and initial distance play a major role in improving high electrical output voltage. PENG- TENG should be improved and optimized to apply and performed as field tests in the real ocean to demonstrate its real potential.
The natural energy harvesting area is a growing research interest to accommodate people's needs. A natural energy harvester's specific objectives to create a new alternative and renewable energy with low cost, environmentally friendly, and easy to maintain have been ongoing progress. Current technologies, specifically in the ocean energy field, have produced sustainability and eco-friendly electricity (Shi et al., 2018). However, many ocean energy converters have a high cost due to huge and complicated structures, high-cost instruments, and high-skilled operators to produce. To efficiently harvest wave and current energy, a new type of harvesting technology is proposed to apply to a Spatio-temporal wider range of energy resources.
Over the last few years, piezoelectric nanogenerators (PENGs) and triboelectric nanogenerators (TENGs) have been used as attractive and useful harvester to produce electric power from ambient energy sources directly. PENG mostly generated electricity from deformation, either by compression (Kim et al., 2020; Zhu et al., 2017) or bending state (Zhang, Hu, & Li, 2019), commonly used in a situation that has a low frequency and high amplitude. Accordingly, PENG is very suitable to be used in various locations under several shapes and sizes. Our previous work with flexible piezoelectric devices (FPED), made with polyvinylidene fluoride (PVDF) film, was able to produce electricity from ocean energy. However, based on those research, the electrical power generation of PENG is very limited. Furthermore, due to the instability in the actual environment (such as ocean energy, wind energy, etc.), PENG is not able to cope with the unsteady vibration external force. As a result, problems such as difficulty in predicting the amount of power generation has, and PENG have not been put into practical use.
