Direct Printing of a Multi-Layer Sensor on Pet Substrate for CO2 Detection

Abstract

The use of inexpensive gas sensors is a real need for many applications requiring the use of disposable sensors. This work deals with the realization and characterization of a low cost CO2 sensor realized by rapid prototyping techniques. In particular, the sensor consists of a set of InterDigiTed electrodes, over which a double sensing layer made of PEDOT/PSS (CLEVIOS™ PHCV4, by H.C.Starck) and a solution of pristine graphene powder has been deposited. A silver nano-particle solution is used for inkjet printing the electrodes onto the PET (PolyEthylene Terephthalate) substrate, through a commercial inkjet printer. The sensing strategy is based on the variation of the electrical conductance of graphene due to gas molecules adsorption. The device responsivity observed in two different operating conditions (50 °C and 60 °C), is 4.0 µΩ/Ω/ppm and 4.7 µΩ/Ω/ppm. The corresponding values of the resolution are 400 ppm and 420 ppm. Main advantages of the developed sensor consist in the cost-effective fabrication techniques and the device flexibility, which are strategic for applications requiring disposable and shapeable devices to be installed into irregular surfaces.

A Flexible and Polymer‐Based Chemiresistive CO2 Gas Sensor at Room Temperature

“…Overall, the advantages and superiority of the proposed polymer may promote the fabricated sensors as a strong candidate for CO 2 sensing compatible with both DC and AC measurements. PEI-functionalized CNTs [48] 200-1000 600 600 Room temperature Yes Yes PEDOT/PSS, graphene [49] 400-4200 NA NA 50 and 60 No Yes…”

A Review on Advanced Sensing Materials for Agricultural Gas Sensors

“…An interesting finding from this study is the added mass of CO during sensing experiments, which was approximately 0.188 pg during a specific experiment, and this number is dependent on factors such as the CO concentration, exposure time (to the analyte) and the volume of sensing material. Shifting focus to CO sensing materials which do not require synthesis within the polymer material class; is the use of graphene and poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT/PSS) in synergy [ 51 ]. Advantages are that both materials are commercially available and do not require any pre-treatment or further synthesis and good working temperature range (35–65 °C).…”

Design and development of original WSN sensor for suspended particulate matter measurements

“…16 very high sensitivity optical instruments for NO x measurement to detect explosives, based on Cavity Ring-Down Spectroscopy with violet laser were presented. Future trend of a low cost sensor, for air quality monitoring was presented [17] where an inkjet printing sensor for CO 2 concentration measurement was described.…”