Flexibility of Fluorinated Graphene-Based Materials

TL;DR

This study investigates how fluorinated graphene-based materials behave under mechanical strains, revealing their potential for flexible electronic applications due to their stable resistive properties and resistive switching under bending.

Contribution

It provides new insights into the strain-dependent electrical properties of fluorinated graphene films, highlighting their suitability for flexible electronics and memristor devices.

Findings

Compressive strain significantly decreases resistivity due to conductive path formation.

Tensile strain causes resistivity to remain stable or increase irreversibly.

Stable bipolar resistive switching observed up to 6.5% tensile strain.

Abstract

The resistivity of different films and structures containing fluorinated graphene (FG) flakes and chemical vapor deposition (CVD) grown graphene of various fluorination degrees under tensile and compressive strains due to bending deformations was studied. Graphene and multilayer graphene films grown by means of the CVD method were transferred onto the flexible substrate by laminating and were subjected to fluorination. They demonstrated a weak fluorination degree (F/C lower 20%). Compressive strains led to a strong (one-two orders of magnitude) decrease in the resistivity in both cases, which was most likely connected with the formation of additional conductive paths through fluorinated graphene. Tensile strain up to 3% caused by the bending of both types of CVD-grown FG led to a constant value of the resistivity or to an irreversible increase in the resistivity under repeated strain cycles. In the case of the structures with the FG thin film printed on polyvinyl alcohol, a stable bipolar resistive switching was observed up to 6.5% of the tensile strain (bending radius was 2 mm). The excellent performance of the crossbar memristor structures under tensile strain shows that the FG films and structures created from suspension are especially promising for flexible electronics.