Films fabricated from partially fluorinated graphene suspension: structural, electronic properties and negative differential resistance

Abstract

The band structure and electric properties of films created from a partially fluorinated graphene suspension are analyzed in this paper. As may be inferred from the structural study, graphene islands (quantum dots) are formed in these films. Various types of negative differential resistance (NDR) and a step-like increase in the current are found for films created from the fluorinated graphene suspension. NDR resulting from the formation of the potential barrier system in the film and corresponding to the theoretical prediction is observed for a relatively low fluorination degree. The origin of the NDR varies with an increase in the fluorination degree of the suspension. The observation of NDR in the fluorinated films widens the range of application of such films, including as active device layers fabricated using 2D printed technologies on rigid and flexible substrates.

Fluorinated Graphene Dielectric and Functional Layers for Electronic Applications

“…Our experiments on the fluorination of CVD grown or mechanically exfoliated graphene in the aqueous solution of hydrofluoric acid also show corrugation of these materials during fluorination. In other words, the corrugation of domain boundaries is an initial driving force for subsequent F reaction with carbon atoms in 2D plain and subsequent corrugation [19,[30][31][32]. This type of reactions stimulated by deformations is also realized for the graphene suspension, and only thin (few layer) flakes are suitable for fluorination during HF treatment.…”

“…It may be connected with varying sizes of graphene islands and existing edge-related defects which provide the possibility of activationless transport in the films. It is worth mentioning that Graphene Materials -Advanced Applicationsthe arrays of QDs formed after similar fluorination of graphene or few layer graphene demonstrate the size quantization levels in Q-DLTS and transport measurements [31,[39][40][41] …”

“…Relation between structural and electronic properties of FG films Figure 5 shows SEM and AFM images of partially fluorinated films, created from the graphene suspension, treated in an aqueous solution of HF for 7 days (~CF 0.10 ) and 20 days (CF 0.23 ) [31]. In both cases, the continuous films consisting of separate flakes may be observed in Figure 5.…”

“…The charge deep level transient spectroscopy (Q-DLTS) and transport measurements were used to characterize partially fluorinated films [31]. It has been found that at the temperature range from 330 to 250 K, the current is described by equation I = I o exp(ÀE/kT), where E = 0.48 eV is the activation energy of the current flow through the film, and k is the Boltzmann constant.…”

FORMIROVANIE I VLIJaNIE BLIZhNEGO PORJaDKA NA SVOJSTVA I HARAKTERISTIKI FTORIROVANNOGO GRAFENA

“…В настоящее время существует достаточное количество теоретических и экспериментальных исследований, посвященных полностью функционализированному фтором графену. Однако работ, посвященных частично фторированному графену, все еще недостаточно, хотя именно в таком графене проявляется аномальное поведение электронных свойств и различных характеристик [2][3][4], обусловленное изменением структуры. Поэтому изучение взаимосвязи структуры и свойств фторированного графена при небольших концентрациях фтора является актуальной задачей.…”