Molecularly Engineered Surface Triboelectric Nanogenerator by Self-Assembled Monolayers (METS)

Self-powered energy harvesters utilizing triboelectric effect and electrostatic induction have been widely studied, leading in the materials viewpoint to numerous material pairs for facile charge separation upon repetitive contacts with elaborate topological structures. Here, we present a simple but robust triboelectric platform based on a molecularly engineered surface triboelectric nanogenerator by self-assembled monolayers (METS). Triboelectric surface charge density of a substrate was readily controlled by the variation of end-functional groups of self-assembled monolayers (SAMs). In particular, by employing fluorine terminated SANIs, we are able to develop a METS with the maximum open circuit voltage and short circuit current of 105 V and 27 mu A, respectively, under relatively gentle mechanical contacts with the 3N vertical force at 1.25 Hz. The power density of the device was 1.8 W/m(2) at the load resistance of 10 M Omega more than 60 times greater than that of an unmodified dielectric/Al device. Moreover, our approach with SAMs was extended to various types of surfaces including fabrics of silk, cotton, and poly(ethylene terephthalate) (PET) and a PET film, and the results of single-friction-surface triboelectric nanogenerators with these materials offers a facile and universal guideline for designing triboelectic materials.