Investigation on the Role of Ionic Liquids in the Output Signal Produced by Bacterial Cellulose-Based Mechanoelectrical Transducers

Abstract

Green sensors are required for the realization of a sustainable economy. Biopolymer-derived composites are a meaningful solution to such a needing. Bacterial Cellulose (BC) is a green biopolymer, with significant mechanical and electrical properties. BC-based composites have been proposed to realize generating mechanoelectrical transductors. The transductors consist of a sheet of BC, impregnated of Ionic Liquids (ILs), and covered with two layers of Conducting Polymer (CP) as the electrodes. Charges accumulate at the electrodes when the transductor is bent. Generating sensors can produce either Open Circuit (OC) voltage or Short Circuit (SC) current. In the paper, the OC voltage and SC current, generated from BC-based composites, in a cantilever configuration and subjected to dynamic deformation are compared. The influence of ILs in the transduction performance, both in the case of OC voltage and SC current is investigated. Experimental investigations of structural, chemical, and mechanoelectrical transduction properties, when the composite is dynamically bent, are performed. The mechanoelectrical investigation has been carried on both in the time and in the frequency domains. Reported results show that no relevant changes can be obtained because of the use of IL when the OC voltage is considered. On the contrary, dramatic changes are observed for the case of SC current, whose value increases by about two orders of magnitude.

Pullulan-1-Ethyl-3-Methylimidazolium Tetrafluoroborate Composite as a Water-Soluble Active Component of a Vibration Sensor

“…Moreover, due to their high solubility in water, they possess characteristics that fall within the realm of transient electronics. Some of our previous works investigated the role of ILs in mechanoelectrical transducers based on bacterial cellulose, further highlighting the potential of polysaccharide-based materials in mechanoelectrical sensing [ 27 , 28 , 29 ].…”

Modeling of Bacterial Cellulose-Based Composite

“…Such a structure has been revealed to be capable of producing an electrical signal when deformed. More specifically, the authors have investigated the role of charges in the IL in the mechanoelectrical transduction phenomenon [29,30]. Beam structures at very low frequencies and up to the mechanical resonant frequency [21,22] have been investigated.…”