Triboelectric Nanogenerator Fabricated from High-Charge-Density, Wear-Resistant MoS2 Nanosheet-PDMS Composite for Energy Harvesting and Motion Detection

Abstract

Triboelectric nanogenerators (TENGs) hold significant potential for a wide range of applications such as harvesting small mechanical energy and enabling self-powered sensing technologies. However, their broader implementation is hindered by limited output performance and a short operational lifespan. This work tackles these challenges by developing a composite film with high charge density and enhanced wear resistance, consisting of molybdenum disulfide (MoS₂) nanosheets and polydimethylsiloxane (PDMS). The 3 wt % MoS₂/PDMS composite film exhibited an 8.8% reduction in friction coefficient compared to pure PDMS. In tribological testing, the composite film showed a significant increase in the number of linear cycles by 146.6% compared to pure PDMS. Under a contact pressure of 8.2 N and an operating frequency of 1.96 Hz, the two-electrode contact-separation mode TENG demonstrated remarkable peak performance metrics: an open-circuit voltage (V_oc) of 410 V, a short-circuit current (I_sc) of 42 μA, and a short-circuit transferred charge (Q_sc) of 76 nC, representing improvements of 2.05, 2.1, and 2.17 times, respectively, compared to a pure PDMS-based TENG. When integrated with a transformer–rectification circuit, the TENG achieved a peak power output of 2.8 mW, sufficient to continuously power capacitors and light up 66 white LEDs. Notably, the TENG maintained stable output performance even after enduring 10,000 operational cycles. An arched TENG design was also created to detect the motion state of the human body. This research offers critical insights and advancements in the design of innovative triboelectric materials for TENG applications, paving the way for enhanced output performance and durability in self-powered systems.