(Keynote) Chemical Selectivity and Micro/Nano Sensors

Abstract

Achieving chemical selectivity in micro and nanosensors is challenging task. Here we describe a technique based on photothermal spectroscopy to enhance the selectivity challenge encountered in nano and micro sensors. This technique does not depend on routinely used method of immobilized chemo-selective molecular layers of sensor surfaces. In this technique physisorbed molecular species on nano and micro sensors are excited into their vibrational levels by sequential exposure to pulsed infrared radiation (IR). Non-radiative decay of the excited species results changes in the temperature of the low thermal mass sensor. Temperature changes of the sensor can be measured by many different methods and when plotted as a function of irradiating IR wavelength shows peaks corresponding to molecular vibrations.