All carbon materials pn diode

Xiaojing Feng,Yong Yan,Xing Zhao,Fengxiang Qie,Tiehu Li,Jiahui Guo,Liu Yang,Yuchun Zhang,Mengyao Li,Wenxia Yuan

doi:10.1038/s41467-018-06150-z

Abstract

Semiconductor pn junctions are elementary building blocks of many electronic devices such as transistors, solar cells, photodetectors, and integrated circuits. Due to the absence of an energy bandgap and massless Dirac-like behaviour of charge carriers, graphene pn junction with electrical current rectification characteristics is hardly achieved. Here we show a graphene pn junction diode can be made exclusively from carbon materials by laminating two layers of positively and negatively charged graphene oxides. As the interdiffusion of oppositely charged mobile counterions, a built-in potential is created to rectify the current by changing the tunnelling probability of electrons across the junction. This graphene diode is semi-transparent, can perform simple logic operations, and since it has carbon nanotubes electrodes, we demonstrate an all carbon materials pn diode. We expect this graphene diode will expand material choices and provide functionalities (e.g. grafting recognition units on graphene oxides) beyond that of traditional semiconductor pn junctions.

Highlights

Semiconductor pn junctions are elementary building blocks of many electronic devices such as transistors, solar cells, photodetectors, and integrated circuits
The key components of the graphene pn junction diode are a layer of negatively charged graphene oxide (GO) and a layer of positively charged GO
Charged GO was synthesized by deprotonating the GO with Tetramethylammonium hydroxide solution ((CH3)4N+OH−, TMAH, pH = 10), while the positively charged GO was synthesized via a two-step procedure[26,27]

Summary

Introduction

Semiconductor pn junctions are elementary building blocks of many electronic devices such as transistors, solar cells, photodetectors, and integrated circuits. As the interdiffusion of oppositely charged mobile counterions, a built-in potential is created to rectify the current by changing the tunnelling probability of electrons across the junction This graphene diode is semi-transparent, can perform simple logic operations, and since it has carbon nanotubes electrodes, we demonstrate an all carbon materials pn diode. In contrast to conventional semiconductors, its conduction and valence bands meet at Brillouin zone corners and, fabricating electronic components from this zero-gap semiconductor should find an unusual way[11] Techniques such as cutting graphene into nanoribbons[12], placing bias on bilayer graphenes[13], and applying mechanical strains[14] were developed to open a bandgap and turn off the current of graphene field-effect transistors. To evaluate the utility of these graphene diodes to build the processing units needed for simple computation, in combination with graphene resistors, all carbon materials AND and OR logic gates were constructed

Methods

Results

Conclusion