Electrical Impedance Spectroscopy for Real-Time Monitoring of the Life Cycle of Graphene Nanoplatelets Filters for Some Organic Industrial Pollutants

Abstract

The paper proposes an approach for a smart monitoring of the life-cycle of innovative graphene-based filters for water remediation in presence of pollutants. The measurement technique is based on suitable figures of merit that analyze the time variation of the electrical impedance frequency spectrum. The proposed study considers the remediation of two toxic industrial pollutants, such as the acetonitrile and the 2,4dichlorophenol. The contribution of the paper is twofold. The first is the demonstration of a reliable monitoring set-up that is able, for the selected use cases, to correlate in real-time the behavior of the electrical impedance of the filter to its status, defined as "absence of pollutants" and/or "saturation". The second contribution is the proposal of suitable figures of merit, based on measurement of the impedance frequency spectrum, able to increase the measurement sensitivity and the reliability and to mitigate some sources of uncertainty typically associated to these kinds of set-ups and measurements.Results show that the proposed graphene-based filters combine very good filtering capability and high sensitivity of the electrical impedance to the considered pollutants. These results suggest further investigations with other pollutants and the potential use of this technique for the predictive maintenance of the water filters in industrial applications, by endowing the graphene filters of smart sensing devices.

MacGyvered Multiproperty Materials Using Nanocarbon and Jam: A Spectroscopic, Electromagnetic, and Rheological Investigation

“…Taking advantage of electrical properties, these nanocomposites could operate as sensors for environmental pollutants. In our previous works, we produced a graphene-based device able to retain and detect organic pollutants in water [ 56 , 57 , 58 ]. Furthermore, by modulating the rheological properties, the nanocomposites could play a role as an epidermal drug release system.…”

Decontamination of surface water from organic pollutants using graphene membranes

“…This article [6] proposed a similar approach, emphasizing the smart monitoring of the life cycle of the same kind of graphene nanoplatelets-based filters for water remediation in the presence of pollutants. The measurement technique was based on suitable figures of merit, analyzing the time variation of the electrical impedance frequency spectrum.…”

Toward Continuous Nano-Plastic Monitoring in Water by High Frequency Impedance Measurement With Nano-Electrode Arrays

“…Systems based on optical methods [23]- [25], radio-frequency resonators [26], [27], and electrochemical impedance spectroscopy (EIS) [28] (sometimes integrating computer vision technology [29], [30]), have been published as well. EIS was also proposed for real-time monitoring of pollutants in graphene filters [31], and capacitive measurement for particle detection in lubricating oil [32]. High Frequency Impedance Spectroscopy (HFIS) with nanoelectrodes (NE) array [33]- [36] is a still largely unexplored (bio)sensing technology, with demonstrated capability to di- rectly detect by purely electrical means single NP as small as 40 nm diameter on top of bovine serum albumin immobilization layer [33].…”