Novel graphene/Sn and graphene/SnOx hybrid nanostructures: Induced superconductivity and band gaps revealed by scanning probe measurements

TL;DR

This study reports the creation of graphene/Sn and graphene/SnOx hybrid nanostructures, revealing induced superconductivity and band gaps through scanning probe measurements, advancing the development of functional superconducting nanomaterials.

Contribution

It introduces a novel fabrication method for graphene/Sn and graphene/SnOx nanostructures and demonstrates their unique electronic properties using scanning probe techniques.

Findings

Superconductivity is induced in graphene supported by Sn NPs.

Sn NPs reduce environmental p-type doping of graphene.

SnOx NPs exhibit a measurable electronic band gap.

Abstract

The development of functional composite nanomaterials based on graphene and metal nanoparticles (NPs) is currently the subject of intense research interest. In this study we report the preparation of novel type of graphene/Sn and graphene/SnOx (1 < x < 2) hybrid nanostructures and their investigation by scanning probe methods. First, we prepare Sn NPs by evaporating 7 - 8 nm tin on highly oriented pyrolytic graphite substrates. Graphene/Sn nanostructures are obtained by transferring graphene on top of the tin NPs immediately after evaporation. We show by scanning tunnelling microscopy (STM) and spectroscopy (STS) that tin NPs reduce significantly the environmental p-type doping of graphene. Furthermore, we demonstrate by low-temperature STM and STS measurements that superconductivity is induced in graphene, either directly supported by Sn NPs or suspended between them. Additionally, we prepare SnOx NPs by annealing the evaporated tin at 500 ${^o}$C. STS measurements performed on hybrid graphene/SnOx nanostructures reveal the electronic band gap of SnOx NPs. The results can open new avenues for the fabrication of novel hybrid superconducting nanomaterials with designed structures and morphologies.