Low Energy Pulsed Laser Excitation in UV Enhances the Gas Sensing Capacity of Photoluminescent ZnO Nanohybrids

Argyro Klini; Maria Androulidaki; Demetrios Anglos

doi:10.3390/s19245490

Low Energy Pulsed Laser Excitation in UV Enhances the Gas Sensing Capacity of Photoluminescent ZnO Nanohybrids

Sensors (Basel). 2019 Dec 12;19(24):5490. doi: 10.3390/s19245490.

Authors

Argyro Klini¹, Maria Androulidaki¹, Demetrios Anglos^{1

2}

Affiliations

¹ Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas P.O. Box 1385, GR 71110 Heraklion, Crete, Greece.
² Department of Chemistry, University of Crete, GR 71003 Heraklion, Crete, Greece.

Abstract

Nanohybrids, composed of luminescent zinc oxide (ZnO) nanoparticles dispersed in an inert polydimethylsiloxane (PDMS) matrix, exhibit an excellent ability to follow changes in the type and composition of their surrounding atmosphere. These changes are found to affect the UV photoluminescence (PL) emission of the ZnO-PDMS hybrids measured at room temperature. The influence of irradiation parameters, such as excitation intensity and wavelength, on the response of the ZnO-PDMS sensor against ethanol and oxygen, have been systematically investigated in a comparative study performed employing pulsed excitation at 248 and 355 nm. This study represents the first demonstration that the sensing performance of the PL-based ZnO sensors can be optimized by tuning the excitation parameters and it particularly illustrates that maintaining a low pump energy density is crucial for enhancing the sensitivity of the sensor achieving response values approaching 100%.

Keywords: ZnO nanoparticles; ZnO photoluminescence; ZnO-PDMS nanocomposite; ethanol sensing; gas sensing; optical sensor; oxygen sensing.