Professor Mona E. Zaghloul (ECE), Dr. S. Semancik (NIST)
We developed a Plasmonic Nano-Hole sensor which was designed and fabricated at the GWU Clean Room. The Nano-Hole diameters is in the range of 200nm. The Plasmonic Nano-Hole could be used for Gas chemical molecules sensing as well as for Biosensor for biomaterial.
The fabricated sensor is highly sensitive. For absorbing the gases molecules metal organic framework (MOF)-coated Nanohole array (NHA) plasmonic sensor array was design and fabricated. The sensor is able to detect concentrations as low as 500 nmol/mol (ppb) of volatile organic compounds (VOCs), such as acetone and ethanol at room temperature. The optical responses at visible wavelengths for this gas sensor using acetone and ethanol at varying concentrations from 500 nmol/mol to 10 umol/mol was tested. Furthermore, a temperature control system was induced to the sensor to study the thermal kinetics of its response as a means of increasing the analytical capabilities of the sensor. Results demonstrated the MOF-coated NHA plasmonic gas sensor can reach limit of detection in the nmol/mol range with rapid response and that temperature dependent kinetic analysis can be applied to discriminate the absorbed gases. To further improve the performance of the sensor, Nano-Holes with smaller dimensions (50 nm) will be fabricated to improve the sensitivity and multi-spots on the response spectra will be studied to increase the selectivity of the sensor.