Silver nanoparticle polymer composite based humidity sensor.
Silver nanoparticles were synthesised by a chemical reduction process in order to produce an aqueous colloidal dispersion. The resulting colloids were then characterised by a combination of UV-Vis spectroscopy, dynamic light scattering, X-ray diffraction and transmission electron microscopy and the nanoparticles were found to have an average diameter of 20-22 nm. The Ag/polymer nanocomposites were then applied to platinum interdigital electrodes as sensor coatings and the capability of the resulting sensor as a humidity detector investigated. With the application of 1 V, a current developed which was found to be directly proportional to humidity levels. The sensor gives a reversible, selective and rapid response which is proportional to levels of humidity within the range of 10% RH to 60% RH. An investigation into the mechanism of the sensor's response was conducted and the response was found to correlate well with a second order Langmuir adsorption model.
School of Chemical and Pharmaceutical Sciences, Dublin Institute of Technology, Kevin St, Dublin, 8, Ireland. aoife.power@dit.ie
Aoife C
AC
Power
Anthony J
AJ
Betts
John F
JF
Cassidy
D055664:Electrochemical Techniques / Q000379:methods*; D004566:Electrodes; D006813:Humidity; D053768:Metal Nanoparticles / Q000737:chemistry*; D010984:Platinum / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D012834:Silver / Q000737:chemistry*; D013227:Steam / Q000032:analysis
D011108:Polymers; D013227:Steam; D012834:Silver; D010984:Platinum