Synergistic effects of porous ferroelectric friction layer and intermediate layers for remarkable performance enhancement of triboelectric nanogenerator

Introducing a porous structure into the friction layer of TENGs is an effective and facile non-additive physical modification method that can increase the contact area during the contact–separation motion. However, the porosity can reduce the charge-storage capacity owing to decreased density. In this study, a TENG was rationally designed by employing a friction layer composed of a porous polyvinylidene fluoride/BaTiO₃ nanoparticle nanocomposite and intermediate layers of polydimethylsiloxane and Cu nanowires to address these limitations. The non-porous friction layer combined with storage and transport layers resulted in a peak-to-peak voltage (V_pp) increase from 30.8 to 84.9 V, while the porous friction layer achieved a significant V_pp enhancement from 75.0 to 206.4 V. This improvement was attributed to the synergistic effect of the increased contact area by the porous friction layer and the enhanced charge-storage capacity provided by the storage layer. The triboelectric charges effectively generated by the increased contact area induced strong electrostatic induction in the charges of the electrode, facilitated by the enhanced charge-storage capacity of the storage layer. Moreover, the transport layer reduced the time required to reach the maximum charge-storage capacity and improved the response speed of the TENG to external mechanical stimuli.