Multilayer sensor for selectively detecting a voc vapor

A method for selectively detecting a volatile organic compound (VOC) vapor, comprising:

• exposing a sensor to an environment in need of detecting the VOC vapor, the sensor comprising
• an insulating substrate,
• a pair of interdigitated electrodes disposed on the insulating substrate,
• a sensing layer of a semi-conductive material disposed on the pair of interdigitated electrodes, the sensing layer exhibiting an electrical property that is dependent on the concentration of the VOC vapor to which the sensing layer is exposed, and
• a filtering layer of a polymer or metal organic framework disposed on the sensing layer, the filtering layer enhancing the selectivity of the sensing layer to the VOC vapor;
• and
• generating a signal when the sensor is exposed to a sample of the VOC vapor having a gas density, gas concentration, or gas partial pressure greater than or equal to the VOC vapor detection threshold of the sensor;
• wherein the sensor has a VOC vapor detection limit that spans a detection range.

A method for producing a sensor for selectively detecting a volatile organic compound (VOC) vapor, comprising:

• depositing a pair of interdigitated electrodes on an insulated substrate;
• depositing a sensing solution to form a sensing layer on the pair of electrodes, wherein the sensing solution comprises a semi-conductive nanoparticle dissolved or suspended in an organic solvent;
• and
• depositing a filtering solution on the sensing layer to form a filtering layer on the sensing layer, wherein the filtering solution comprises a polymer or metal organic framework dissolved or suspended in an organic solvent.