Chen, ChenWen, ZhenWei, AiminXie, XinkaiZhai, NingningWei, XuelianPeng, MingfaLiu, YinaSun, XuhuiYeow, John2019-09-262019-09-262019-08https://doi.org/10.1016/j.nanoen.2019.05.029http://hdl.handle.net/10012/15170The final publication is available at Elsevier via https://doi.org/10.1016/j.nanoen.2019.05.029. © 2019. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/Ion concentration in water is a key criterion for evaluating water quality. In this work, we developed a self-powered on-line ion concentration monitor in water transportation based on impedance matching effect of triboelectric nanogenerator (TENG). A rotary disc-shaped TENG (RD-TENG) and an ion concentration sensor were fabricated based on the industrial printed circuit board (PCB) technology. Flowing water in the pipeline acts as the energy source to drive the RD-TENG and generate an open-circuit (Voc) of 210 V. The ion concentration sensor exhibits a nearly pure resistance characteristic under the alternating current (AC) signal with the frequency below 500 Hz, corresponding to the rotation speed of 250 rpm for the RD-TENG. The impedance matching relationship between the RD-TENG and the ion concentration sensor was experimentally studied and applied to elucidate the sensing mechanism. Finally, a self-powered sensing system integrated with an alarm circuit was assembled which exhibits excellent responsibility and high sensitivity. The change of ion concentration with only 1 × 10−5 mol/L can light up an alarm LED.enAttribution-NonCommercial-NoDerivatives 4.0 Internationalhttp://creativecommons.org/licenses/by-nc-nd/4.0/triboelectric nanogeneratorself-poweredimpedance matching effection concentration monitorArticle