Organically interconnected graphene flakes: A flexible 3-D material with tunable electronic bandgap

E Klontzas,V Varshney,E Tylianakis,G E Froudakis,A K Roy

doi:10.1038/s41598-019-50037-y

Abstract

The structural and electronic properties of molecularly pillared graphene sheets were explored by performing Density Functional based Tight Binding calculations. Several different architectures were generated by varying the density of the pillars, the chemical composition of the organic molecule acting as a pillar and the pillar distribution. Our results show that by changing the pillars density and distribution we can tune the band gap transforming graphene from metallic to semiconducting in a continuous way. In addition, the chemical composition of the pillars affects the band gap in a lesser extent by introducing additional states in the valence or the conduction band and can act as a fine band gap tuning. These unique electronic properties controlled by design, makes Mollecular Pillared Graphene an excellent material for flexible electronics.

Highlights

During the last seven decades there has been a huge growth in the development of new electronic devices, which enabled for the development of new technologies and new markets globally
The pillars were covalently bonded to the graphene through the formation of five-member boroxine rings as originally synthesized in the Graphene Oxide Framework (GOF)[14] and Covalent-Organic Framework (COF) materials[41]
We have examined a set of molecularly pillared graphene networks by varying both the pillar density and the chemical composition of the pillar molecule in terms of electronic properties by performing Tight Binding Density Functional Theory (TB-DFT) calculations

Summary

Introduction

During the last seven decades there has been a huge growth in the development of new electronic devices, which enabled for the development of new technologies and new markets globally. Besides the efforts to improve the performance with respect to the above mentioned factors, there have been a lot of efforts to build electronic devices with better mechanical flexibility, giving rise to an emerging research field of flexible and stretchable electronics[1]. Flexible electronic materials is considered as one of the most emergent research areas nowadays since there is a tremendous need to build low cost, large area electronic devices with the ability to be incorporated on flexible substrates. They can be categorized as either inorganic or organic based materials with their own unique properties in terms of intrinsic flexibility, carrier density and carrier mobility. It has been shown that such modifications can effectively adjust the electronic properties of the corresponding materials

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Results

Conclusion