Electrical Switching in Thin Films of Nandi Flame Seed Cuticles

Abstract

Current-voltage () characteristics of Nandi flame seed cuticles (NFSCs) have been studied as a function of irradiation, annealing, and poling temperature. The cuticles showed memory and threshold switching. Threshold voltage was about 5 V which is almost five times higher than observed in synthetic polymers. The threshold voltage increased to 6–8 V after irradiation and annealing depending on the duration of annealing or irradiation. After switching, conductivity increased by an order of . In reverse bias, increase of current was observed and the memory hysteresis loop was at higher conductivity than at the time of switching. Switching effect was minimized at a poling temperature of 370 K. Formation of semiquinones and quinoid radicals from phenolic compounds may have contributed to electrical switching and hysteresis effect.

Electrically conductive bioplastics based on chitosan, polyvinyl alcohol, polyvinyl pyrrolidone, and plant extract nanoparticles for detecting Rhizopus stolonifer on tomato fruit

“…Additionally, Kipnusu et al 54 explained that the most likely source of conductance switching in Nandi flame seed cuticles ( Spathodea campanulate ) was the formation of quinoid and semiquinone structures resulting from phenolic compound oxidation in plant cuticles. These electrical switching molecules have one or more phenyl rings and semiquinone structures that allow for an easy proton‐electron transfer within the molecules, giving a flow of charges.…”

Charge Transport Mechanism in Thin Cuticles Holding Nandi Flame Seeds

“…Polymers which exhibit electrical switching and memory effect can also be applied in electrical switching circuit and in gas sensing [ 36 ]. Electrical switching is explained in terms of formation of semiquinones and quinoid radicals [ 3 ] and in terms of SCLC. As shown in Figure 5(a) , the low current densities at low voltages is due to charge capture in traps (intrinsic charges) present in the cuticle.…”

“…Plant cuticle membranes have been found to contain high proportions of insoluble and acid resistant cutin biopolyester [ 2 ]. Current-voltage characteristics of Nandi flame seed cuticle biomaterial have shown electrical switching and memory properties [ 3 ]. Conducting biomaterials have been demonstrated to be potentially useful in making eco-friendly electronic devices and probes for sensors fabrication [ 4 – 7 ], solid electrolyte systems [ 8 ], barrier materials, and controlled release polymers [ 9 ], and in tissue engineering because they can easily be used as a platform that supports electrical stimulation of cell-tissue constructs [ 10 ].…”