Chemiresistor-based gas sensors for detection of target volatile organic compounds (VOCs) in air face common challenges of poor sensitivity and selectivity as well as suffering from interference by other constituent gases and/or humidity. This work demonstrates that functionalizing gold nanoparticles (AuNPs) with a designed thiol monolayer improves sensitivity and selectivity of the derived AuNPs gas sensor. We report the synthesis and application of a thiol ligand fitted with both a urea motif and a tert-butyl end group for functionalizing AuNPs. The AuNPs sensor prepared using the urea thiol ligand demonstrated significantly increased acetone sensing in comparison with tested commercially available thiol-functionalized AuNPs. The sensor worked under ambient temperature and high humidity conditions, and demonstrated a linear relationship between the sensor response and the common logarithm of analyte concentration.
Bibliographical noteFunding Information:
We gratefully acknowledge nancial support by NIH (P42 ES023716).
This work was supported by the Science and Technology Commission of Shanghai Municipality (16JC1400700), the Program for Changjiang Scholars and Innovative Research Team in University (IRT-16R13) and the Ministry of Science and Technology, Taiwan, China (MOST 106-2221-E-009-130-MY3 Program).We gratefully acknowledge financial support by NIH (P42 ES023716).