Aiming to detect ammonia vapor, polypyrrole (PPy) thin layers were in situ coated on AT-cut 10 MHz quartz crystal microbalance QCM electrode by a facile chemical polymerization process using two organic acids as dopants, i.e. dodecylbenzene sulfonic acid (BDSA) and 1–5 naphthalene disulfonic acid (NDSA). Then after, polymers structural and morphological features were determined by FTIR, Raman spectroscopy and Scanning Electron Microscopy (SEM) techniques. Ammonia vapor sensing tests were related to QCM frequency changes recorded upon vapor adsorption and desorption on PPy films, it was found that frequency shifts varied linearly with both vapor concentration expressed in part per million (ppm) and polymer’s thin layer thickness given in nanometer (nm). This fact has been assumed to be mainly related to the electrostatic interactions established between ammonia vapor molecules and the polymer dopant agents. Tests have shown that films based PPy/NDSA exhibit high sensitivity around 3 ppm and detection limit of 4 ppm over films based PPy/DBSA. Interestingly, an excellent recovery time less than 3 min has been also recorded with PPy/NDSA thin layers. Moreover, when applying Fick’s second law, they have also shown a high diffusion constant.
Journal of Polymer Research – Springer Journals
Published: Mar 14, 2018
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.
All for just $49/month
Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly
Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.
All the latest content is available, no embargo periods.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud