Enhanced and selective acetone sensing properties of SnO2-MWCNT nanocomposites: Promising materials for diabetes sensor

Achieving good sensitivity toward low ppm acetone with pronounced resolution is a challenging, yet very much required task for the development of breath analyzer to monitor diabetes in a non-invasive way. We were able to achieve high sensitivity, stability, ultrafast response toward sub-ppm acetone with a good resolution just by using MWCNTs as a substrate for nanocrystalline SnO2 prepared through a facile sol-gel technique. The composites were well characterized using XRD and TEM/HRTEM which revealed not only the structure and purity of the samples but also indicates the successful integration of MWCNT with SnO2 nanoparticles. The composite sensor showed much better performance at the lower temperature than pure SnO2. Enhancement of adsorption ability of SnO2 due to the addition of MWCNTs, and the difference between their work function, could be collectively responsible for the improvement of sensing activity. Besides, these nanocomposite sensors also showed much-reduced cross-sensitivity toward moisture, which is a major component of human exhale breath. This will be an extra-advantage of MWCNT incorporation for developing breath analyzer to monitor diabetes using SnO2 nanocomposites based sensor.