Highly monodispersed mesoporous, heterojunction ZnO@Au micro-spheres for trace-level detection of NO2 gas

Dinesh Veeran Ponnuvelu, Sukhananazerin Abdulla, Biji Pullithadathil*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

Abstract

Highly monodispersed, mesoporous ZnO@Au heterojunction micro-spheres have been successfully synthesized using a two-stage facile chemical method and their surface bound NO2 sensing properties were explored. Room temperature Photoluminescence (RTPL) reveal the presence of high degree of oxygen defects and zinc interstitials for the pristine ZnO mesoporous-spheres and a drastic reduction in PL intensity of the ZnO@Au heterojunction mesoporous-spheres pointing towards the utilization of surface defects for the Au cluster growth, facilitating electron transfer process between ZnO and Au. NO2 gas sensor property analysis of the ZnO@Au mesoporous-spheres showed an extraordinary sensitivity and selectivity at a lower operating temperature of 250 °C than pristine ZnO mesoporous-spheres (450 °C). The enhanced sensing behavior of the ZnO@Au heterojunction mesoporous-spheres can be ascribed to the synergetic effect of Au nanoclusters at the heterojunctions which acts as spill-over zone for the physisorption mediated sensing process and the inherent high surface area and surface defects.

Original languageEnglish
Pages (from-to)156-165
Number of pages10
JournalMicroporous and Mesoporous Materials
Volume255
DOIs
StatePublished - 2018
Externally publishedYes

Keywords

  • Chemiresistive NO gas sensor
  • Heterojunction
  • Mesoporous materials
  • ZnO@Au

Fingerprint

Dive into the research topics of 'Highly monodispersed mesoporous, heterojunction ZnO@Au micro-spheres for trace-level detection of NO2 gas'. Together they form a unique fingerprint.

Cite this