Pulsed laser deposition of ZnO thin films decorated with Au and Pd nanoparticles with enhanced acetone sensing performance

TL;DR

This study develops pulsed laser deposited ZnO thin-film sensors decorated with Au and Pd nanoparticles, demonstrating significantly improved acetone detection sensitivity and lower detection limits at relatively low operating temperatures.

Contribution

It introduces a novel fabrication method for nanocomposite ZnO sensors with Au and Pd nanoparticles, showing enhanced acetone sensing performance compared to pure ZnO sensors.

Findings

ZnO:Pd sensors outperform ZnO:Au sensors.

Detection limit for acetone is 26 ppm at 200°C.

Sensor response increases with Pd amount.

Abstract

We fabricate and compare nanocomposite thin-film ZnO chemoresistive acetone sensors with gold or palladium nanoparticles on the surface, at low operating temperatures. The sensors are fabricated by pulsed laser deposition and operate in the temperature range 159-200oC. The ZnO films are polycrystalline, crystallizing mainly at the (002) and (101) orientations of the hexagonal phase. The nanocomposite ZnO:Au and ZnO:Pd sensors have a lower detection limit and show a response enhancement factor between 2-7, compared with pure ZnO sensors. The ZnO:Pd sensor performs better than the ZnO:Au sensor. The ZnO:Pd sensor sensitivity increases with the amount of palladium on the surface, while it remains roughly unchanged with the ZnO thickness. The lowest acetone concentration we detect is 26 ppm for the operating temperature of 200oC.