Substrate-Independent Catalyst-Free Synthesis of High-Purity Bi2Se3 Nanostructures

TL;DR

This paper presents a catalyst-free vapor-solid method for synthesizing high-purity Bi2Se3 nanostructures on various substrates, demonstrating their robustness and potential for device integration.

Contribution

A novel substrate-independent, catalyst-free synthesis technique for high-purity Bi2Se3 nanostructures with diverse morphologies and confirmed stability on flexible substrates.

Findings

High chemical purity of synthesized nanostructures

Surface states contribute to electronic properties

Robustness on flexible mica substrates

Abstract

We describe a catalyst-free vapor-solid synthesis of bismuth selenide (Bi2Se3) nanostructures at ambient pressure with hydrogen as a carrier gas. The nanostructures were synthesized on glass, silicon and mica substrates and the method yields a variety of nanostructures: nanowires, nanoribbons, nanoplatelets and nanoflakes. The materials analysis shows high chemical purity in all cases, without sacrificing the crystalline structure of Bi2Se3. Low-temperature measurements of the nanostructures indicate contributions from the surface states with a tunable carrier density. Samples synthesized on flexible mica substrates show no significant change in resistance upon bending, indicating robustness of as-grown Bi2Se3 nanostructures and their suitability for device applications.