Atypical electrical behavior of few layered WS2 nanosheets based platform subject to heavy metal ion treatment

TL;DR

This study reports the reversible atypical electrical behavior of few-layer WS2 nanosheets upon heavy metal ion treatment, highlighting potential applications in sensing technologies.

Contribution

It introduces a novel reversible electrical response of WS2 nanosheets to heavy metal ions, expanding understanding of their sensing capabilities.

Findings

Heavy metal ions induce non-ohmic I-V behavior in WS2 nanosheets.

The atypical electrical behavior is reversible after ion removal.

The phenomenon suggests potential for sensor development.

Abstract

An atypical electrical behavior of WS2 nanosheets deposited on Cu electrodes is reported here. The characteristic Raman peaks at 355cm-1 and 421.8cm-1 confirm the few-layer structure of WS2. The addition of heavy metal ions of ~30 micro Liter on this platform results in non-ohmic behavior in I-V characteristics, accompanied by a dramatic rise of current from nA to micro Ampere Additionally, this atypical behavior is found to be reversible. Subsequent to removal of these ions from the nanosheets, it again exhibits normal ohmic I-V characteristics. It is envisioned that this unusual characteristic will pave way for more research in the sensing direction as well as relevant fields.