Chemiresistor
![A basic schematic of a single gap chemiresistive sensor.](/Images/godic/202501/04/Chemiresistor_diagram_14110.jpg")
![An oxygen sensing TiO2 film on an interdigitated electrode.
Wang,
H., Chen, L., Wang, J., Sun, Q., & Zhao, Y. (2014). A micro oxygen sensor
based on a nano sol-gel TiO2 thin film. Sensors (Basel), 14(9), 16423.
doi:10.3390/s140916423](/Images/godic/202501/04/Interdigitated_electrode_with_film4110.jpg")
![Circular interdigitated electrodes with and without a gold nanoparticle chemiresistor film](/Images/godic/202501/04/Circular_interdigitated_electrodes_with_and_without_gold_nanoparticle_chemiresistor_film4110.jpg")
![Polymerization of a polymer around a target molecule that is then washed out to leave shaped cavities behind.](/Images/godic/202501/04/MIP_drawing4110.jpg")
A chemiresistor is a material that changes its electrical resistance in response to changes in the nearby chemical environment. Chemiresistors are a class of chemical sensors relies on the direct chemical interaction between the sensing material and the analyte. The chemical interaction between the sensing material and the analyte can vary from a covalent interaction, to hydrogen bonding interactions, to shape recognition. Several different materials have chemiresistor properties: metal oxide semiconductors, some conductive polymers, and nanomaterials like graphene, carbon nanotubes and nanoparticles. Typically these materials are used as partially selective sensors in devices like electronic tongues or electronic noses.