Triboelectric nanogenerators (TENGs) and piezoelectric generators (PGs) are generally considered the two most common approaches for harvesting ambient mechanical energy that is ubiquitous in our everyday life. The main difference between the two generators lies in their respective working frequency range. Despite the remarkable progress, there has been no quantitative studies on the operating frequency band of the two generators at frequency values below 4 Hz, typical of human motion. Here, the two generators are systematically compared based on their energy harvesting capabilities below 4 Hz. Unlike PGs, the TENG demonstrates higher power performance and is almost independent of the operating frequency, making it highly efficient for multi-frequency operation. In addition, PGs were shown to be inapplicable for charging capacitors when a rectifier was attached to the system. The results of this work reveal the tremendous potential of flexible TENGs for harvesting energy at low frequency.

摩擦纳米发电机（TENG）和压电发电机（PG）通常被认为是收集我们日常生活中无处不在的环境机械能的两种最常见的方法。两种发生器的主要区别在于各自的工作频率范围。尽管取得了显着的进展，但尚未对这两个发生器在低于 4 Hz（人体运动的典型频率）的频率值下的工作频段进行定量研究。在这里，根据 4 Hz 以下的能量收集能力对这两种发电机进行了系统比较。与 PG 不同，TENG 表现出更高的功率性能，并且几乎独立于工作频率，使其能够高效地进行多频操作。此外，当系统连接整流器时，PG 不适用于为电容器充电。这项工作的结果揭示了柔性 TENG 在低频能量收集方面的巨大潜力。