Contact Electrification at the Liquid–Solid Interface

Abstract

Interfaces between a liquid and a solid (L–S) are the most important surface science in chemistry, catalysis, energy, and even biology. Formation of an electric double layer (EDL) at the L–S interface has been attributed due to the adsorption of a layer of ions at the solid surface, which causes the ions in the liquid to redistribute. Although the existence of a layer of charges on a solid surface is always assumed, the origin of the charges is not extensively explored. Recent studies of contact electrification (CE) between a liquid and a solid suggest that electron transfer plays a dominant role at the initial stage for forming the charge layer at the L–S interface. Here, we review the recent works about electron transfer in liquid–solid CE, including scenerios such as liquid–insulator, liquid–semiconductor, and liquid–metal. Formation of the EDL is revisited considering the existence of electron transfer at the L–S interface. Furthermore, the triboelectric nanogenerator (TENG) technique based on the liquid–solid CE is introduced, which can be used not only for harvesting mechanical energy from a liquid but also as a probe for probing the charge transfer at liquid–solid interfaces.

Hybrid film for liquid‐solid contact‐based energy harvesting systems

“…However, the incorporation of PTFE particles decreases the surface wettability due to the formation of nanostructures on the surface, which increases the surface hydrophobicity and allows accelerated movement of droplets on the surface as well as easy detachment of the liquid layer from the surface. 27 Moreover, PTFE contains the highly electronegative fluorine atoms, which attracts electron during contact with other material and thus increases the output performance during contact electrification. 24,45 Therefore, the films with the addition of PTFE particles show better output performance than the pristine PDMS film.…”

“…The decrease in the output performance of the device at low pH is mainly due to the presence of the H + ions in the solution, which adsorbs on the surface and causes hindrance in the electron transfer. 27,41,51…”

A Triboelectric Nanogenerator Based on Sodium Chloride Powder for Self-Powered Humidity Sensor

“…However, there are still many challenges in energy harvesting efficiency and use environment. In addition, the high preparation cost is also an important reason to hinder its application in distributed sensor networks [10]. In recent years, with the development of energy storage technology, distributed sensor network nodes usually provide power by electronics.…”

A Novel Triboelectric Material Based on Deciduous Leaf for Energy Harvesting

“…As we all know, friction motion widely exists in the environment; therefore, TENG's acquisition of friction mechanical energy is widespread. Through a simple power generation device design and friction movement, TENG can collect almost all mechanical energy, such as wind energy, water drop energy, wave energy, human motion energy, and other mechanical energy, and convert it into electrical energy [13][14][15][16][17][18][19][20][21].…”