Performance enhancement of polysiloxane-based nanocomposite TENGs through optimized MWCNT concentration

This study examines the effect of multi-walled carbon nanotube (MWCNT) loading on the dielectric behavior and triboelectric performance of polysiloxane (PS)-based nanocomposites for high-efficiency triboelectric nanogenerators (TENGs).

Flexible PS/MWCNT films were fabricated using the doctor blading method and characterized by Raman spectroscopy and scanning electron microscopy (SEM). Broadband dielectric spectroscopy was employed to analyze frequency-dependent permittivity, interfacial polarization, and dielectric loss. TENGs were assembled in a vertical contact-separation mode using nylon as the positive triboelectric layer and evaluated under controlled temperature and humidity. Statistical error analysis (n = 3) was applied to ensure quantitative reliability.

A co-optimal MWCNT concentration of 0.03-0.05 wt% enhanced dielectric permittivity and interfacial charge trapping, improving triboelectric output while keeping conductive losses low. Higher loadings led to nanotube aggregation and increased dielectric loss, degrading device performance.

The study establishes a quantitative correlation between dielectric spectroscopy and triboelectric output, providing mechanistic insight into performance enhancement and degradation. This framework offers practical guidelines for designing PS-based nanocomposite TENGs for wearable electronics, self-powered sensors, and portable energy-harvesting applications.