Triboelectric nanogenerators (TENGs) offer a self-sustaining power solution for marine regions abundant in resources but constrained by energy availability. Since their pioneering use in wave energy harvesting in 2014, nearly a decade of advancements has yielded nearly thousands of research articles in this domain. Researchers have developed various TENG device structures with diverse functionalities to facilitate their commercial deployment. Nonetheless, there is a gap in comprehensive summaries and performance evaluations of TENG structural designs. This paper delineates six innovative structural designs, focusing on enhancing internal device output and adapting to external environments: high space utilization, hybrid generator, mechanical gain, broadband response, multi-directional operation, and hybrid energy-harvesting systems. We summarize the prevailing trends in device structure design identified by the research community. Furthermore, we conduct a meticulous comparison of the electrical performance of these devices under motorized, simulated wave, and real marine conditions, while also assessing their sustainability in terms of device durability and mechanical robustness. In conclusion, the paper outlines future research avenues and discusses the obstacles encountered in the TENG field. This review aims to offer valuable perspectives for ongoing research and to advance the progress and application of TENG technology.

Interface functional groups play an essential role in regulating the electrical properties of bulk materials. In this work, we designed a novel strategy to explore a new way to enhance triboelectric performance by regulating the functional groups between nano-fillers and polymer matrix without obvious changes in the dielectric constant. The silica nanoparticles (SNPs) modified perfluoro-silane coupling agents (PFSCAs) with different chain lengths were added to the polyvinylidene difluoride to regulate the transferred charge density (TCD) of triboelectric nanogenerators (TENGs). When the doping concentration of perfluorodecyl modified SNPs is 2.25 wt.%, the nanocomposite film based TENG exhibits the maximum TCD of 166 µC/m² and power density of 3.12 W/m² which are 6 times and 39 times as big as those of pure polyvinylidene difluoride (PVDF) film. The charge accumulation and decay process show that interface functional groups dominate the performance of TENGs. Then, a Fermi level model is proposed and why the TCD could be regulated by the concentration of nanoparticles in bulk materials is explained. This work provides a new concept for understanding the performance of TENG independent dielectric constant and points out a new direction for enhancing TENG’s performance, since wealthy functional groups with selectivity are applicable.

The output power of the triboelectric nanogenerator (TENG) strongly depends on the performance of triboelectric materials, especially microstructures and functional groups of them. In this work, aiming at the excellent triboelectric ability, alternate-layered MXene composite films-based TENG with abundant fluorine groups(-F) through layer-by-layer stacking are designed and fabricated. Benefitting from the uniform intrinsic microstructure and increased dielectric constant, when the amount of the Nb₂CT_x nanosheets increases to 15 wt%, the TENG based on Nb₂CT_x/Ti₃C₂T_x composite nanosheets films achieves the maximum output. The short-circuit current density of 8.06 μA/cm² and voltage of 34.63 V are 8.4 times and 3.5 times over that of pure Ti₃C₂T_x films, and 3.3 times and 4.3 times over that of commercial poly(tetrafluoroethylene) (PTFE) films, respectively. Furthermore, the fabricated TENG could be attached to human body to harvest energy from human motions, such as typing, texting, and hand clapping. The results demonstrate that the alternate-layered MXene composite nanosheet films through layer-by-layer stacking possess remarkably triboelectric performance, which broaden the choice of negative triboelectric materials and supply a new choice for high output TENG.

Triboelectric–electromagnetic hybrid nanogenerators (TE-HNGs) are promising for efficient energy harvesting, particularly from high-energy-density water waves. However, existing TE-HNGs often suffer from mechanical combinations and lack comprehensive energy optimization strategies, resulting in a suboptimal overall effect where 1 + 1 ≤ 2. Herein, a highly coupled energy self-managed power system (ESPS) is proposed based on our meticulously designed multilayer magnetic suspension hybrid nanogenerator (MS-HNG) with triboelectric and electromagnetic units. Due to voltage phase coherence between the generators, the magnetic suspension electromagnetic generator (MS-EMG) serves as the gate drive source for metal oxide semiconductor field-effect transistors, enabling the instantaneous release of energy from the magnetic suspension triboelectric nanogenerator (MS-TENG) and thereby maximizing energy output within each cycle. The ESPS achieves a peak power of 261.3 mW, a significant improvement over 75.5 mW from the MS-HNG alone, illustrating a synergistic effect where 1 + 1 > 2. Additionally, the ESPS achieves a current of 45 mA (a 7500% increase) and a power density of 631 W m⁻³ (a 346% increase). In water wave environments, this system can power 32 bulbs of 3 W each and perform water quality monitoring. This work represents a new breakthrough in the structural and circuit coupling of TE-HNGs, marking a milestone towards commercialization.

The ocean, with its highly variable and complex meteorological conditions, harbors enormous renewable resources. Triboelectric nanogenerators (TENGs), which possess unique advantages, show exciting prospects in water wave energy collection. How to design and optimize TENGs to cover all characteristic water wave energies and achieve efficient energy utilization is emergent. In this paper, we carefully designed and fabricated a columnar multi-layer sliding TENG (CMLS-TENG) that can harvest water wave energy independent of wave height and direction. Drive rods with a hollow acrylic spherical shell were introduced to deliver wave energy, ensuring that the CMLS-TENG can work in all directions from 0° to 360°. Based on the sliding structure, switching the optimized CMLS-TENG is independent of wave heights. The optimized CMLS-TENG can achieve a total power density of 730 mW/m³ at a wave height of only 4.8 cm regardless of wave direction, which can illuminate multiple light-emitting diodes (LEDs) to provide lighting and provide power to a watch and a hygrometer for temperature and humidity monitoring. This work provides new choices and hopes for the effective collection of full-range water wave energy.