Chemical electrification at solid/liquid/air interface by surface dipole of self-assembled monolayer and harvesting energy of moving water

Abstract

Harvesting energy from water motion is attractive and is considered as a promising component in a microgenerator system for decentralized energy. Recent developments have been shown to rely on spontaneous electrification at the solid-liquid interface, even though the precise mechanism is still under debate. In this paper, we report that the triple-phase boundary of solid/liquid/air can be quantitatively charged by tuning the work function by modifying a self-assembled monolayer (SAM), where a permanent or redox-active dipole controls the polarity and degree of electrification, and by modulating the electrochemical potential of the solution used. With the simple system proposed here, electricity is successfully delivered to turn on a light-emitting diode (LED), demonstrating the potential applicability of the system for energy harvesters. (c) 2022 Elsevier Inc. All rights reserved.